TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumExample
2.A.1.1:  The Sugar Porter (SP) Family
2.A.1.1.1









Galactose:H+ symporter (also transports xylose) (Hernández-Montalvo et al., 2001). Relative substrate affinities of wild-type and mutant forms of the E. coli sugar transporter GalP have been determined by solid-state NMR (Patching et al., 2008).

Bacteria
Proteobacteria
GalP of E. coli (P0AEP1)
2.A.1.1.2









Arabinose (xylose; galactose):H+ symporter
Bacteria
Proteobacteria
AraE of E. coli (P0AE24)
2.A.1.1.3









Xylose:H+ symporter.  Also transports and binds D-glucose and 6-bromo-6-deoxy-D-glucose.  The 3-d structure is known in three conformers, outward occluded, inward occluded and inward open (Sun et al. 2012: Quistgaard et al. 2013).  Most of the sugar-binding residues are conserved with the human Glut-1, 2, 3 and 4 homologues.  The coalescence of intramolecular tunnels and cavities has been postulated to account for facilitated diffusion of sugars (Quistgaard et al. 2013).  Most of the sugar-binding residues are conserved with the human Glut-1, 2, 3 and 4 homologues.  The coalescence of intramolecular tunnels and cavities has been postulated to account for facilitated diffusion of sugars (Cunningham and Naftalin 2014).

Bacteria
Proteobacteria
XylE of E. coli (P0AGF4)
2.A.1.1.4









Glucose uniporter
Bacteria
Proteobacteria
Glf of Zymomonas mobilis
2.A.1.1.5









Hexose uniporter
Eukaryota
Fungi
HxtO of Saccharomyces cerevisiae
2.A.1.1.6









Galactose, glucose uniporter, Gal2. Also transports xylose (Wang et al. 2013).  This transporter has been engineered by mutation (N376F) to transport xylose without being inhibited by glucose or transporting other hexoses (Farwick et al. 2014).  The 3-d structure is known (Wang et al. 2015).

Eukaryota
Fungi
Gal2 of Saccharomyces cerevisiae
2.A.1.1.7









Quinate:H+ symporter
Eukaryota
Fungi
Qay of Neurospora crassa
2.A.1.1.8









Myoinositol:H+ symporter

 

 

Eukaryota
Fungi
ITR1 of Saccharomyces cerevisiae
2.A.1.1.9









Lactose, galactose:H+ symporter
Eukaryota
Fungi
LacP of Kluyveromyces lactis
2.A.1.1.10









Maltose:H+ symporter
Eukaryota
Fungi
MAL6 of Saccharomyces cerevisiae
2.A.1.1.11









General α-glucoside H+ symporter
(Trehalose, maltose turanose, isomaltose, α-methyl-glucoside, maltotriose, palatinose, trehalose and melezitose): H+ symporter, Gtr3 or Agt1 (Smit et al., 2008).
Eukaryota
Fungi
AGT1 of Saccharomyces cerevisiae
2.A.1.1.12









Glucose uniporter (also transports dehydro-ascorbate; Maulén et al., 2003). Down-regulated in the brains of Alzheimer's disease patients (Liu et al., 2008b).

Eukaryota
Metazoa
Gtr3 (Glut3) of Rattus norvegicus (rat)
2.A.1.1.13









Fructose uniporter
Eukaryota
Metazoa
SLC2A5 of Homo sapiens
2.A.1.1.14









Hexose:H+ symporter
Eukaryota
Viridiplantae
Hup1 of Chlorella kessleri
2.A.1.1.15









Putative sugar transporter
Archaea
Crenarchaeota
Porter of Sulfolobus solfataricus
2.A.1.1.16









Low-affinity hexose (glucose, fructose, mannose, 2-deoxyglucose) uniporter.  The evolution of hexose transporters in kinetoplastid protozoans has been studied (Pereira and Silber 2012).

Eukaryota
Kinetoplastida
Gtr2 (D2) of Leishmania donovani
2.A.1.1.17









Glucose transporter
Eukaryota
Fungi
Th2A of Trypanosoma brucei
2.A.1.1.18









Glucose/mannose/fructose transporter and high affinity sensor, Snf3p (regulates glucose transport via other systems).  REsidues involved in ligand preference are similar to those involved in transport (Dietvorst et al. 2010).

Eukaryota
Kinetoplastida
Snf3p of Saccharomyces cerevisiae
2.A.1.1.19









Glucose transporter and low affinity sensor, Rgt2p (regulates glucose transport in conjunction with Snf3p)

Eukaryota
Fungi
Rgt2p of Saccharomyces cerevisiae
2.A.1.1.20









Myoinositol:H+ symporter, MIT
Eukaryota
Kinetoplastida
MIT of Leishmania donovani; most similar to ITRI of Saccharomyces cerevisiae
2.A.1.1.21









Hexose:H+ symporter, Ght2 (Glucose > Fructose)
Eukaryota
Fungi
Ght2 of Schizosaccharomyces pombe
2.A.1.1.22









Hexose:H+ symporter, Ght6 (Fructose > Glucose)
Eukaryota
Fungi
Ght6 of Schizosaccharomyces pombe
2.A.1.1.23









Gluconate:H+ symporter, Ght3
Eukaryota
Fungi
Ght3 of Schizosaccharomyces pombe
2.A.1.1.24









Hexose (Glucose and Fructose) transporter, PfHT1
Eukaryota
Apicomplexa
PfHT1 of Plasmodium falciparum
2.A.1.1.25









Myoinositol:H+ symporter, HMIT (also transport other inositols including scyllo-, muco- and chiro-, but not allo-inositol) (Aouameur et al., 2007). Expressed in the golgi of the hippocampus and cortex. May also transport inositoltriphosphate (Di Daniel et al., 2009).

Eukaryota
Metazoa
SLC2A13 of Homo sapiens
2.A.1.1.26









Major myoinositol:H+ symporter, IolT
Bacteria
Firmicutes
IolT (YdjK) of Bacillus subtilis
2.A.1.1.27









Minor myoinositol:H+ symporter, IolF
Bacteria
Firmicutes
IolF of Bacillus subtilis
2.A.1.1.28









The erythrocyte/brain hexose facilitator, Gtr1 or Glut1. Also transports D-glucose, dehydroascorbate, arsenite and the flavonone, quercetin, via one channel and water via a distinct channel. Sugar transport has been suggested to function via a sliding mechanism involving several sugar binding sites (Cunningham et al., 2006). Glut1 is the receptor for human T-cell leukemia virus (HTLV)) (Manel et al., 2003). It is regulated by stomatin to take up dehydroascorbate (Montel-Hagen et al., 2008). Mutations cause Glut1 deficiency syndrome, a human encephalopathy that results from decreased glucose flux through the blood brain barrier (Pascual et al., 2008). Mueckler and Makepeace (2009) have presented a model of the exofacial substrate-binding site and helical folding of Glut1. Glut 1, 2, 4 and 9 are functional both in the plasma membrane and the endoplasmic reticulum (Takanaga and Frommer, 2010). Glut1 is down-regulated in the brains of Alzheimer's disease patients (Liu et al., 2008b). Metabolic stress rapidly stimulates blood-brain barrier endothelial cell sugar transport by acute up-regulation of plasma membrane GLUT1 levels, possibly involving an AMP-activated kinase activity (Cura and Carruthers, 2010). Serves as a receptor for neuropilin-1 (923aas; 2 TMSs) (O14786) and heparan sulfate proteoglycans (HSPGs) (Hoshino, 2012). Glut1 has a nucleotide binding site, and nucleotide binding affects transport activity (Yao and Bajjalieh 2009).

Eukaryota
Metazoa
SLC2A1 of Homo sapiens
2.A.1.1.29









Glucosamine/glucose uniporter, Glut-2 (may also transport dehydroascorbate (Mardones et al., 2011Maulén et al., 2003), and cotransport water against an osmotic gradient (Naftalin, 2008))

Eukaryota
Metazoa
SLC2A2 of Homo sapiens
2.A.1.1.30









Low affinity, constitutive, glucose (hexose; xylose) uniporter, Hxt4 (LGT1) (also transports arsenic trioxide [As(OH)3] as do Hxtl, 3, 5, 7 and 9) (Liu et al., 2004)
Eukaryota
Fungi
Hxt4 of Saccharomyces cerevisiae
2.A.1.1.31









High affinity, glucose-repressible, glucose (hexose) uniporter (Hxt6/Hxt7). Asn331 and hydrophobic residue side chains in TMS5 determine substrate affinity (Kasahara et al., 2011; Kasahara and Kasahara 2010).  Also transports xylose (Kasahara and Kasahara 2010).  Also transports xylose (Wang et al. 2013).

Eukaryota
Fungi
Hxt6/Hxt7 of Saccharomyces cerevisiae
Hxt6 (P39003)
2.A.1.1.32









Glucose/fructose:H+ symporter, GlcP (Zhang et al., 1989)
Bacteria
Cyanobacteria
GlcP of Synechocystis sp. (P15729)
2.A.1.1.33









Fructose:H+ symporter, Frt1 (Diezemann and Boles, 2003)
Eukaryota
Fungi
Frt1 of Kluyveromyces lactis (CAC79614)
2.A.1.1.34









The broad specificity sugar/sugar alcohol (myo-inositol, glycerol, ribose, sorbitol, mannitol, xylitol, erythritol, etc) H+ symporter, AtPLT5 (transports a wide range of hexoses, pentoses, tetroses, sugar alcohols and a sugar acid, but not disaccharides) (Reinders et al., 2005) (expressed in roots, leaves and floral organs) (Klepek et al., 2004)
Eukaryota
Viridiplantae
AtPLT5 of Arabidopsis thaliana (Q8VZ80)
2.A.1.1.35









The major glucose (or 2-deoxyglucose) uptake transporter, GlcP (van Wezel et al., 2005)
Bacteria
Actinobacteria
GlcP of Streptomyces coelicolor (Q7BEC4)
2.A.1.1.36









The low affinity, glucose-inducible glucose transporter, MstE (Forment et al., 2006)

Eukaryota
Fungi
MstE of Aspergillus nidulans (Q400D8)
2.A.1.1.37









The glucose/fructose facilitator, Glut7 (SLC2A7) (a single mutation, I314V, results in loss of fructose transport but retention of glucose transport (Manolescu et al., 2005)
Eukaryota
Metazoa
SLC2A7 of Homo sapiens
2.A.1.1.38









The glycerol:H+ symporter, Stl1p (Ferreira et al., 2005)
Eukaryota
Fungi
Stl1p of Saccharomyces cerevisiae (NP_010825)
2.A.1.1.39









The high affinity glucose transporter, Hgt1 (Baruffini et al., 2006)
Eukaryota
Fungi
Hgt1 of Kluyveromyces lactis (P49374)
2.A.1.1.40









The xylose facilitator, Xylhp (Nobre et al., 1999)
Eukaryota
Fungi
Xylhp of Debaryomyces hansenii (AAR06925)
2.A.1.1.41









The D-xylose:H+ symporter, XylT (Km=220 μM; inhibited competitively by 6-deoxyglucose (Ki=220 μM), but not by other sugars tested) (Chaillou et al., 1998)
Bacteria
Firmicutes
XylT of Lactobacillus brevis (O52733)
2.A.1.1.42









The D-glucose:H+ symporter, GlcP (glucose uptake is inhibited by 2-deoxyglucose, mannose and galactose) (Parche et al., 2006)
Bacteria
Actinobacteria
GlcP of Bifidobacterium longum (AAN25419)
2.A.1.1.43









The monosaccharide (MST) (glucose > mannose > galactose > fructose):H+ symporter, MST1 (Schussler et al., 2006).

Eukaryota
Fungi
MST1 of Geosiphon pyriformis (A0ZXK6)
2.A.1.1.44









The hexose (glucose and fructose but not galactose) transporter (Glut11; SLC2A11) (Scheepers et al., 2005)
Eukaryota
Metazoa
SLC2A11 of Homo sapiens
2.A.1.1.45









Vacuolar (tonoplast) glucose transporter1, Vgt1 (important for seed germination and flowering) (Aluri and Büttner, 2007)

Eukaryota
Viridiplantae
Vgt1 of Arabidopsis thaliana (Q8L6Z8)
2.A.1.1.46









The blastocyst/testis glucose transporter, Glut8 (Doege et al., 2000) (insulin stimulated in blastocysts) (Carayannopoulos et al., 2000).

Eukaryota
Metazoa
Glut8 of Mus musculus (Q9JIF3)
2.A.1.1.47









The liver, kidney, and other tissue embryonic uric acid transporter, Glut9 (SLC2A9) (Wright et al. 2010). Mutations in this transporter cause severe renal hyperuricemia.

Eukaryota
Metazoa
Glut9 of Mus musculus (Q5ERC7)
2.A.1.1.48









The pentose/hexose transporter (sugar transport protein 2), STP2. (Expressed during pollen maturation and early stages of gametophyte development) (Truernit et al., 1999)
Eukaryota
Viridiplantae
STP2 of Arabidopsis thaliana (Q9LNV3)
2.A.1.1.49









The sink-specific, stress-regulated monosaccharide uptake porter, STP4. (Induced upon wounding or infection with bacteria or fungi; expressed in roots and flowers) (Truernit et al., 1996)
Eukaryota
Viridiplantae
STP4 of Arabidopsis thaliana (Q39228)
2.A.1.1.50









The glucose/fructose:H+ symporter, STP13. Expressed in vascular tissues and induced during programmed cell death (Norholm et al., 2006)
Eukaryota
Viridiplantae
STP13 of Arabidopsis thaliana (Q94AZ2)
2.A.1.1.51









Glucose/xylose: H+ symporter, Gsx1 (Leandro et al., 2006)
Eukaryota
Fungi
Gsx1 of Candida intermedia (Q2MEV7)
2.A.1.1.52









The glucose transport protein, GTP1 (Skelly et al., 1994)
Eukaryota
Metazoa
GTP1 of Schistosoma mansoni (Q26579)
2.A.1.1.53









Myo-Inositol uptake porter, IolT1 (Km=0.2mM) (Krings et al., 2006).  Can also transport D-glucose (Ikeda et al. 2011).

Bacteria
Actinobacteria
IolT1 of Corynebacterium glutamicum (Q8NTX0)
2.A.1.1.54









Myo-Inositol (Km=0.45mM) uptake porter, IolT2 (Krings et al., 2006).  Can not transport D-glucose (Ikeda et al. 2011).

Bacteria
Actinobacteria
IolT2 of Corynebacterium glutamicum (Q8NL90)
2.A.1.1.55









L-arabinose:proton symporter, AraE (Sa-Nogueira and Ramos, 1997). Also transports xylose, galactose and α-1,5 arabinobiose (Ferreira and Sá-Nogueira, 2010).

Bacteria
Firmicutes
AraE of Bacillus subtilis (P96710)
2.A.1.1.56









High affinity monosaccharide (KM ≈ 20 µM):H+ symporter, Stp6 (takes up glucose, 3-O-methylglucose, mannose, fructose, galactose and to a lesser extent, xylose and ribulose. (Scholz-Starke et al., 2003)
Eukaryota
Viridiplantae
Stp6 of Arabidopsis thaliana (Q9SFG0)
2.A.1.1.57









High affinity (15 μM) glucose (monosaccharides including xylose):H+ symporter, MstA (Jørgensen et al., 2007).

Eukaryota
Fungi
MstA of Aspergillus niger
(Q8J0V1)
2.A.1.1.58









Low affinity glucose:H+ symporter, MstC (Jørgensen et al., 2007).

Eukaryota
Fungi
MstC of Aspergillus niger
(Q8J0U9)
2.A.1.1.59









The glucose transporter, GLUT10, was originally believed to be responsible for Type 2 diabetes. It is now believed to be responsible for arterial tortuosity, a rare autosomal recessive connective tissue disease (Callewaert et al., 2007). GLUT10 transports glucose and 2-deoxy glucose (Km=0.3 mM), and is inhibited by galactose and phloretin (Coucke et al., 2006).
Eukaryota
Metazoa
SLC2A10 of Homo sapiens
2.A.1.1.60









The major hexose transporter, Htr1 (mediates the active uptake of hexoses by sugar:H+ symport. Can transport glucose, 3-O-methylglucose, fructose, xylose, mannose, galactose, fucose, 2-deoxyglucose and arabinose. Confers sensitivity to galactose in seedlings. Km=20 uM for glucose) (Stadler et al., 2003; Boorer et al., 1994)
Eukaryota
Viridiplantae
Htr1 of Arabidopsis thaliana (P23586)
2.A.1.1.61









High affinity monosaccharide (Km = 25 µM) transporter (takes up glucose, galactose, mannose, xylose and 3-O-methylglucose, but not fructose and ribose), STP11 (expressed in pollen tubes) (Schneidereit et al., 2005)
Eukaryota
Viridiplantae
STP11 of Arabidopsis thaliana (Q9FMX3)
2.A.1.1.62









High affinity (0.24mM) plasma membrane myoinositol-specific H+ symporter, INT4 (Schneider et al., 2006)
Eukaryota
Viridiplantae
INT4 of Arabidopsis thaliana (O23492)
2.A.1.1.63









Low affinity inositol (myoinsoitol (Km = 1 mM), scylloinositol, d-chiroinositol and mucoinositol):H+ symporter (expressed in the anther tapetum, the vasculature, and the leaf mesophyll (Schneider et al., 2007)
Eukaryota
Viridiplantae
INT2 of Arabidopsis thaliana (Q9C757)
2.A.1.1.64









The hexose sensor, Hxs1 (believed to be non-transporting) (Stasyk et al., 2008)
Eukaryota
Fungi
Hxs1 of Hansenula polymorpha (B1PM37)
2.A.1.1.65









Glucose permease GlcP (Pimentel-Schmitt et al., 2008) (most similar to 2.A.1.1.32)
Bacteria
Actinobacteria
GlcP of Mycobacterium smegmatis (A0QZX3)
2.A.1.1.66









The tonoplast H+:Inositol symporter 1, Int1 (mediates efflux from the tonoplast to the cytoplasm (Schneider et al., 2008) (most similar to 2.A.1.1.63 and 2.A.1.1.62).

Eukaryota
Viridiplantae
Int1 of Arabidopsis thaliana (Q8VZR6)
2.A.1.1.67









Glucose/xylose facilitator-1, GXF1 (functions by sugar uniport; low affinity (Leandro et al., 2008)
Eukaryota
Fungi
GXF1 of Candida intermedia (Q2MDH1)
2.A.1.1.68









The Glucose Transporter/Sensor Rgt2

Eukaryota
Fungi
Rgt2 Pichia stipitis (A3M0N3)
2.A.1.1.69









Sugar & polyol transporter 1 (SPT1): broad specificity; takes up glucose (Schilling and Oesterhelt, 2007). Loss of the first 3 TMSs of the 12 TMSs does not prevent sugar uptake or sugar recognition but lowers substrate affinity & transport rate, and abolished H+ symport (Schilling and Oesterhelt, 2007).
Eukaryota
Bangiophyceae
SPT1 of Galdieria sulphuraria (A1Z264)
2.A.1.1.70









MFS Permease

Eukaryota
Fungi
MFS Permease of Phaeosphaeria nodurum
2.A.1.1.71









Hexose (glucose) transporter, GT4 (D2) (almost identical to 2.A.1.1.16)
Eukaryota
Kinetoplastida
Hexose transporter, GT4 of Leishmania mexicana (B1PLM1)
2.A.1.1.72









The kidney basolateral voltage-driven urate efflux transporter (URATv1) (orthologue of 2.A.1.1.47) (Anzai et al., 2008). Human SLC2A9a and SLC2A9b isoforms mediate electrogenic transport of urate with different characteristics in the presence of hexoses (Witkowska et al., 2012).

Eukaryota
Metazoa
SLC2A9 of Homo sapiens
2.A.1.1.73









Glycerol uptake permease (Glycerol:H+ symporter) Stl1. (Involved in salt stress relief) (Kayingo et al. 2009) (similar to Stl1 of S. cerevisiae (2.A.1.1.38))
Eukaryota
Fungi
Stl1 of Candida albicans (Q5A8J5)
2.A.1.1.74









The putative L-rhamnose porter, RhaY

Bacteria
Firmicutes
RhaY of Listeria monocytogenes (Q926Q9)
2.A.1.1.75









The fructose/xylose:H+ symporter, PMT1 (polyol monosaccharide transporter-1). Also transports other substrates at lower rates. PMT2 is largely of the same sequence and function. Both are present in pollen and young xylem cells (Klepek et al., 2005).

Eukaryota
Viridiplantae
PMT1 of Arabidopsis thaliana (Q9XIH7)
2.A.1.1.76









Glucose transporter, GT1. GT1, 2, and 3 are homologues. GT2 and GT3 transport ribose as well as glucose at different rates. GT3 transports ribose with 6-fold lower efficiency due to two threonines in GT3 that are alanines in GT2. They are in two loops between TMSs 3, 4, and 7, 8 (Naula et al., 2010).

Eukaryota
Kinetoplastida
GT1 of Leishmania mexicana (Q9F315)
2.A.1.1.77









The D-glucose/D-ribose transporter, LmGT2 (Most similar to 1.A.1.1.18) (Naula et al., 2010).

Eukaryota
Kinetoplastida
LmGT2 of Leishmania mexicana (O61059)
2.A.1.1.78









The glucose transporter, LmGT3 (homologous to LmGT2 (1.A.1.1.75)). Two threonine residues located in the hydrophilic loops connecting TMSs 3 & 4 and 7 & 8 of GT3 prevent transport of D-ribose. Changing these two residues to alanine (as in GT2) allows transport of ribose. Thus, loops 3-4 and 7-8 partially determine substrate specificity (Naula et al., 2010).

Eukaryota
Kinetoplastida
LmGT3 of Leishmania mexicana (O61060)
2.A.1.1.79









Polyol (xylitol):H+ symporter, PLT4 (Kalliampakou et al., 2011)

 

Eukaryota
Viridiplantae
PLT4 of Lotus japonicus (Q1XF07)
2.A.1.1.80









Insulin-responsive facilitative glucose transporter in skeletal and cardiac muscle, adipose, and other tissues, Glut4 (GTR4; SLC2A4; 509aas). Defects in Glut4 cause noninsulin-dependent diabetes mellitus (NIDDM). Hyperinsulinemia leads to uncoupled insulin regulation of the GLUT4 glucose transporter and the FoxO1 transcription factor (Gonzalez et al., 2011). The first luminal loop confers insulin responsiveness to GLUT4 (Kim and Kandror, 2012). Exercise increases Glut4 synthesis in a process involving several protein kinases, the Glut4 enhancer factor (GEF; SLC2A4 regulator; Q9NR83), and the myocyte enhancing factor 2 (MEF2; NP_001139257). (McGee and Hargreaves 2006; Wright 2007; Zorzano et al. 2005)

Eukaryota
Metazoa
SLC2A4 of Homo sapiens
2.A.1.1.81









The glucose uptake porter, GluP (Araki et al., 2011).

Bacteria
Actinobacteria
GluP of Rhodococcus jostii (Q0SE66)
2.A.1.1.82









The cellobiose/cellodextrin transporter, Cdt-1 (Galazka et al., 2010)

Eukaryota
Fungi
Cdt-1 of Neurospora crassa (Q7SCU1)
2.A.1.1.83









The cellobiose/cellodextrin transporter, Cdt-2

Eukaryota
Fungi
Cdt2 of Neurospora crassa (Q7SD12)
2.A.1.1.84









The heteromeric TMT1/TMT2 glucose/sucrose:H+ antiporter. Catalyzes glucose/sucrose antiport into vacuoles (Schulz et al., 2011).

Eukaryota
Viridiplantae
The TMT1/2 sugar:H+ anti-porter of Arabidopsis thaliana. TMT1 (Q96290). TMT2 (Q8LPQ8).
2.A.1.1.85









Zebrafish Slc2A10 (Glut10) facilitative glucose transporter.

Eukaryota
Metazoa
Zebrafish Glut10 of Danio rerio (A8KB28)
2.A.1.1.86









The sea bream facilitative glucose transporter 1 (GLUT1) (Balmaceda-Aguilera et al., 2012).

Eukaryota
Metazoa
Glut1 of Sparus aurata (H9BPB6)
2.A.1.1.87









solute carrier family 2 (facilitated glucose transporter), member 12
Eukaryota
Metazoa
SLC2A12 of Homo sapiens
2.A.1.1.88









solute carrier family 2 (facilitated glucose transporter), member 6
Eukaryota
Metazoa
SLC2A6 of Homo sapiens
2.A.1.1.89









Solute carrier family 2, facilitated glucose transporter member 8 (Glucose transporter type 8) (GLUT-8) (Glucose transporter type X1)
Eukaryota
Metazoa
SLC2A8 of Homo sapiens
2.A.1.1.90









Solute carrier family 2, facilitated glucose transporter member 14 (Glucose transporter type 14) (GLUT-14)
Eukaryota
Metazoa
SLC2A14 of Homo sapiens
2.A.1.1.91









Solute carrier family 2, facilitated glucose transporter member 3 (Glucose transporter type 3, brain) (GLUT-3)
Eukaryota
Metazoa
SLC2A3 of Homo sapiens
2.A.1.1.92









Inner membrane metabolite transport protein YdjE

Bacteria
Proteobacteria
YdjE of E. coli
2.A.1.1.93









Vacuolar protein sorting-associated protein 73
Eukaryota
Fungi
VPS73 of Saccharomyces cerevisiae
2.A.1.1.94









Putative metabolite transport protein YDL199C
Eukaryota
Fungi
YDL199C of Saccharomyces cerevisiae
2.A.1.1.95









Inner membrane metabolite transport protein YgcS

Bacteria
Proteobacteria
 YgcS of E. coli
2.A.1.1.96









Probable metabolite transport protein YBR241C
Eukaryota
Fungi
YBR241C of Saccharomyces cerevisiae
2.A.1.1.97









Sugar transporter ERD6 (Early-responsive to dehydration protein 6) (Sugar transporter-like protein 1)
Eukaryota
Viridiplantae
ERD6 of Arabidopsis thaliana
2.A.1.1.98









Sugar transporter ERD6-like 6
Eukaryota
Viridiplantae
At1g75220 of Arabidopsis thaliana
2.A.1.1.99









Facilitated trehalose transporter Tret1-1 (DmTret1-1)
Eukaryota
Metazoa
Tret1-1 of Drosophila melanogaster
2.A.1.1.100









Probable metabolite transport protein YFL040W
Eukaryota
Fungi
YFL040W of Saccharomyces cerevisiae
2.A.1.1.101









Probable metabolite transport protein YDR387C
Eukaryota
Fungi
YDR387C of Saccharomyces cerevisiae
2.A.1.1.102









Plastidic glucose transporter 4 (AtpGlcT)
Eukaryota
Viridiplantae
At5g16150 of Arabidopsis thaliana
2.A.1.1.103









D-xylose-proton symporter-like 3, chloroplastic
Eukaryota
Viridiplantae
At5g59250 of Arabidopsis thaliana
2.A.1.1.104









Myo-inositol transporter 2
Eukaryota
Fungi
ITR2 of Saccharomyces cerevisiae
2.A.1.1.105









Hexose transporter HXT11 (Low-affinity glucose transporter LGT3)
Eukaryota
Fungi
HXT11 of Saccharomyces cerevisiae
2.A.1.1.106









Probable metabolite transport protein CsbC
Bacteria
Firmicutes
CsbC of Bacillus subtilis
2.A.1.1.107









Hexose transporter HXT15
Eukaryota
Fungi
HXT15 of Saccharomyces cerevisiae
2.A.1.1.108









Low-affinity glucose transporter HXT1
Eukaryota
Fungi
HXT1 of Saccharomyces cerevisiae
2.A.1.1.109









Hexose transporter HXT14
Eukaryota
Fungi
HXT14 of Saccharomyces cerevisiae
2.A.1.1.110









Hexose transporter HXT13
Eukaryota
Fungi
HXT13 of Saccharomyces cerevisiae
2.A.1.1.111









High-affinity glucose transporter HXT2.  Asp340 in part determines the glucose affinity (Kasahara and Kasahara 2010).

Eukaryota
Fungi
HXT2 of Saccharomyces cerevisiae
2.A.1.1.112









High-affinity glucose transporter Ght1 (Hexose transporter 1)
Eukaryota
Fungi
Ght1 of Schizosaccharomyces pombe
2.A.1.1.113









Putative metabolite transport protein YyaJ

Bacteria
Firmicutes
YyaJ of Bacillus subtilis
2.A.1.1.114









Putative metabolite transport protein YaaU

Bacteria
Proteobacteria
YaaU of Escherichia coli
2.A.1.1.115









Putative metabolite transport protein YdjK

Bacteria
Proteobacteria
YdjK of Escherichia coli
2.A.1.1.116









Arabinose/xylose transporter, AraE (Wang et al. 2013).

Bacteria
Actinobacteria
AraE of Coynebacterium glutamicum
2.A.1.1.117









Glucose transporter Rco-3 or MoST1. MoST1 plays a specific role in conidiation and mycelial melanization which is not shared by other hexose transporter family members in M. oryzae (Saitoh et al. 2013).

Eukaryota
Fungi
MoST1 of Magnaporthe oryzae
2.A.1.1.118









MFS porter of 435 aas

Archaea
Crenarchaeota
MFS porter of Sulfolobus solfataricus
2.A.1.1.119









The galacturonic acid (galacturonate) uptake porter, GatA, of 518 aas and 12 TMSs (Sloothaak et al. 2014).

Eukaryota
Fungi
GatA of Aspergillus niger
2.A.1.1.120









Major myo-inositol transporter, IolT1, of 456 aas (Kröger et al. 2010).

Bacteria
Proteobacteria
IolT1 of Samonella enterica
2.A.1.1.121









Minor myo-inositol transporter, IolT2, of 478 aas (Kröger et al. 2010).

Bacteria
Proteobacteria
IolT2 of Salmonella enterica
2.A.1.1.122









Sorbitol (glucitol) transporter SOT2 of 491 aas (Liu D and Teng Y, unpublished)

SOT2 of Pyrus pyrifolia (Chinese pear) (Pyrus serotina)
2.A.1.1.123









Sorbitol transporter of 535 aas

SOT1 of Pyrus pyrifolia (Chinese pear) (Pyrus serotina)
2.A.1.2:  The Drug:H+ Antiporter-1 (12 Spanner) (DHA1) Family
2.A.1.2.1









Pyridoxine, pyridoxal, pyridoxamine, amiloride:H+ cotransporter (Km (pyridoxine) = 22 μM) (Stolz et al., 2005). Also takes up thiamine (Vogl et al., 2008).

Eukaryota
Fungi
Bsu1 (Car1) of Schizosaccharomyces pombe (P33532)
2.A.1.2.2









Cycloheximide:H+ antiporter
Eukaryota
Fungi
CyhR of Candida maltosa
2.A.1.2.3









Chloramphenicol:H+ antiporter, CmlA; Cmr; MdfA.  Multidrug exporter that also catalyzes efflux of arabinose (but not xylose) and  isopropyl β-thiogalactoside (Koita and Rao 2012).

Bacteria
Proteobacteria
CmlA of Pseudomonas aeruginosa
2.A.1.2.4









Tetracycline:H+ antiporter
Bacteria
Proteobacteria
TetA of E. coli
2.A.1.2.5









Multidrug (14- and 15-membered macrolides, lincosamides, streptogramins, tetracyclines, daunomycin, ethidium bromide, etc.):H+ antiporter, LmrP. Two proton translocation pathways have been proposed (Bapna et al., 2007), but Schaedler and van Veen, 2010 have provided evidence that a flexible cation binding site in LmrP is associated with variable proton coupling. Basic residues R260 and K357 affect the conformational dynamics of LmrP (Wang and van Veen, 2012).  Basic residues, R260 and K357 control the conformational dynamics of the protein (Wang and van Veen 2012).  Also specifically catalyzes Ca2+:3H+ antiport with an affinity of 7 μM (Zhang et al. 2012). Two carboxylates (Asp-235 and Glu-327) are critical for Ca2+ binding.  Protonation drives major conformational switches (Masureel et al. 2013).

 

Bacteria
Firmicutes
LmrP of Lactococcus lactis
2.A.1.2.6









(Benomyl, cycloheximide, methotrexate, fluconazole, etc.):H+ antiporter, CaMDR1 (Basso et al., 2010; Cannon et al., 1998). MDR1 catalyzes efflux of commonly used azoles. The central cytoplasmic loop is critical for MDR function, but does not impart substrate specificity (Mandal et al., 2012).

Eukaryota
Fungi
CaMDR1 of Candida albicans
2.A.1.2.7









(Bicyclomycin, sulfathiazole, tetracycline, fosfomycin, acriflavin, etc.):H+ antiporter. Also exports L-cysteine (Yamada et al., 2006).

Bacteria
Proteobacteria
Bcr of E. coli
2.A.1.2.8









(Spermidine; fluoroquinolones, acriflavin, chloramphenicol, ethidium bromide, etc.):H+ antiporter
Bacteria
Firmicutes
Blt of Bacillus subtilis
2.A.1.2.9









(Hydrophobic uncoupler e.g., CCCP, benzalkonium, SDS):H+ antiporter, EmrD. The 3-d structure (3.5 Å resolution) has been determined (Yin et al., 2006).  conformational dynamics studies have revealed details of the transport pathway and some motions of EmrD at an atomic level (Baker et al. 2012).  Probably exports arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
EmrD of E. coli
2.A.1.2.10









Quinolone (and other drug):H+ antiporter
Bacteria
Firmicutes
NorA of Staphylococcus aureus (P0A0J7)
2.A.1.2.11









Monoamine transporter; drug (doxorubicin, ethidium bromide-6-G):H+ antiporter
Eukaryota
Metazoa
VMAT1 of Rattus norvegicus
2.A.1.2.12









Chromaffin granule monoamine (and drug) transporter, VAT1
Eukaryota
Metazoa
SLC18A1 of Homo sapiens
2.A.1.2.13









Vesicular acetylcholine:H+ antiporter, UNC-17/VAChT.  Mutants grow slowly and are uncoordinated, but the defect can be corrected by mutation of an interacting monotopic protein, SUP-1 (Mathews et al. 2012). 

Eukaryota
Metazoa
Unc17 of Caenorhabditis elegans
2.A.1.2.14









Putative arabinose efflux porter
Bacteria
Proteobacteria
AraJ of E. coli
2.A.1.2.15









Arabinose (but not xylose) and isopropyl β-D-thio-galactopyranoside:H+ antiporter, YdeA (Koita and Rao 2012).

Bacteria
Proteobacteria
YdeA of E. coli
2.A.1.2.16









Polyamines (spermine, spermidine, putrescene); paraquat; methylgloxal bis(guanylhydrazone):H+ antiporter (in the plasma membrane) (activated by phosphorylation) (Uemura et al., 2005)
Eukaryota
Fungi
TPO1 (YLL028w) of Saccharomyces cerevisiae
2.A.1.2.17









Fluconazole:H+ antiporter
Eukaryota
Fungi
Flr1 of Saccharomyces cerevisiae
2.A.1.2.18









Lactose and melibiose (>>IPTG) efflux pump, SotB
Bacteria
Proteobacteria
SotB of Erwinia chrysanthemi
2.A.1.2.19









The multidrug (chloramphenicol, tetra-
cycline, norfloxacin, doxorubicin, trimethoprim, acriflavin, ethidium bromide, tetraphenylphosphonium, TPP, benzalkonium, ciprofloxacin, thiamphenicol, IPTG) resistance exporter, MdfA (catalyzes both electrogenic and electroneutral transport) (Adler and Bibi, 2004). Can function as a Na (K )/H antiporter (Lewinson and Bibi 2001; Higgins, 2007). For review of MdfA see Lewinson et al., 2006. The conformational switch accompanying transport is induced by promiscuous binding of substrates and/or inhibitors to the binding pocket (Fluman et al., 2009). Normally extrudes monovalent cationic drugs in exchange for a single proton, but it transports divalent cationic drugs poorly. It can be mutated to antiport a divalent cationic drug for 2 protons (Tirosh et al., 2012).

Bacteria
Proteobacteria
MdfA of E. coli (P0AEY8)
2.A.1.2.20









Putative MDR efflux pump, MdtG (YceE) (under SoxSR control) (Fàbrega et al., 2010). (May confer fosfomycin- and fluoroquinolone-resistance)

Bacteria
Proteobacteria
MdtG of E. coli
2.A.1.2.21









The norfloxacin/enoxacin resistance protein, MdtH or YceL (Nishino and Yamaguchi 2001).

Bacteria
Proteobacteria
MdtH OR YceL of E. coli (P69367)
2.A.1.2.22









The chloramphenicol resistance protein,
YidY
Bacteria
Proteobacteria
YidY of E. coli
2.A.1.2.23









The fructose-specific facilitator (uniporter), Ffz1 (Pina et al., 2004)
Eukaryota
Fungi
Ffz1 of Zygosaccharomyces bailii (CAD56485)
2.A.1.2.24









The multidrug resistance efflux pump, CgMDR (exports fluoroquinolones and chloramphenicol) (Vardy et al., 2005)
Bacteria
Actinobacteria
CgMDR of Corynebacterium glutamicum (NP_600365)
2.A.1.2.25









The purine base/nucleoside (nucleosides: inosine, adenosine and guanosine; bases: hypoxanthine adenine, guanine 2-fluoroadenine) efflux pump, YdhL (PbuE) (Johansen et al., 2003; Nygaard and Saxild, 2005; Zakataeva et al., 2007; Sheremet et al. 2011Sheremet et al. 2011).

Bacteria
Firmicutes
PbuE of Bacillus subtilis (O05504)
2.A.1.2.26









The purine ribonucleoside (inosine, adenosine, guanosine, 6-mercaptopurine ribonucleoside) efflux pump (H+ antiporter), NepI (YicM) (Gronskiy et al., 2005; Sheremet et al. 2011)

Bacteria
Proteobacteria
NepI of E. coli (P0ADL1)
2.A.1.2.27









The alcaligin siderophore exporter, AlcS (Brickman and Armstrong, 2005)
Bacteria
Proteobacteria
AlcS of Bordetella pertussis (CAE42734)
2.A.1.2.28









The vesicular acetylcholine transporter, VAChT (pumps acetylcholine into synaptic vesicles).  The acetyl choline and vesamicol binding sites are near the luminal end of the transport pathway (Khare et al. 2010).

Eukaryota
Metazoa
SLC18A3 of Homo sapiens
2.A.1.2.29









The vesicular monoamine transporter, VMAT2 (pumps dopamine, norepinephrine, serotonin and histamine into synaptic vesicles). VMAT2 physically and functionally interacts with the enzymes responsible for dopamine synthesis (Cartier et al., 2010).  Molecular hinge points mediating alternating access have been identified (Yaffe et al. 2013).

Eukaryota
Metazoa
VMAT2 (SLC18A2) of Homo sapiens
2.A.1.2.30









The hippocampus abundant transcript-like 1 protein, HIATL1 (putative drux exporter)
Eukaryota
Metazoa
HIATL1 of Homo sapiens (NP_115947)
2.A.1.2.31









The multidrug transporter, QDR2, required for resistance to quinidine, barban, cisplatin, and bleomycin; may have a role in potassium uptake
Eukaryota
Fungi
QDR2 of Saccharomyces cerevisiae (P40474)
2.A.1.2.32









The chloramphenicol resistance protein, ChlR
Bacteria
Actinobacteria
ChlR of Streptomyces lividans (P31141)
2.A.1.2.33









The Hol1 MFS transporter (Mutation allows the uptake of histidinol and other cations (Wright et al., 1996). The N-terminal 200 residues show 22% identity with 2.A.1.2.1 and 2.A.1.2.16).
Eukaryota
Fungi
Hol1 of Saccharomyces cerevisiae (P53389)
2.A.1.2.34









The MDR efflux pump, PmrA (exports fluoroquinolone and other compounds) and other components including the antimicrobial peptide, colistin (Martinez-Garriga et al. 2007; Pamp et al., 2008).

Bacteria
Firmicutes
PmrA of Streptococcus pneumoniae (P0A4K4)
2.A.1.2.35









The caffeine resistance protein 5 (Caf5) (Benko et al., 2004)

Eukaryota
Fungi
Caf5 of Schizosaccharomyces pombe (O94528)
2.A.1.2.36









The multidrug resistance protein Aqr1 (YNL065w) (exports short chain monocarboxylates but not more hydrophobic acids such as octonate and quinidine. Also exports ketoconazole and crystal violet (Tenreiro et al., 2002)).
Eukaryota
Fungi
Aqr1 of Saccharomyces cerevisiae (P53943)
2.A.1.2.37









The legiobactin (siderophore) exporter (most similar to 2.A.1.2.9; 23% identity) (Allard et al., 2006)
Bacteria
Proteobacteria
IbtB of Legionella pneumophila
LbtA (Q45RG2)
LbtB (Q5WX21)
2.A.1.2.38









Tetracycline-specific exporter, TetA39 (most like 2.A.1.2.4) (Thompson et al., 2007).
Bacteria
Proteobacteria
TetA39 of Acinetobacter spp. (Q56RY7)
2.A.1.2.39









Tetracycline-specific exporter, TetA41 (most like 2.A.1.2.4) (Thompson et al., 2007).
Bacteria
Proteobacteria
TetA41 of Serratia marcescens (Q5JAK9)
2.A.1.2.40









The dityrosine exporter, Dtr1 (required for formation of the outer layer of the cell wall (Morishita and Engebrecht, 2008)).
Eukaryota
Fungi
Dtr1 of Saccharomyces cerevisiae (P38125)
2.A.1.2.41









The tetracycline resistance determinant, TetA42 from a deep terrestrial subsurface bacterium (Brown et al., 2008).
Bacteria
Actinobacteria
TetA42 of Micrococcus sp. SMCC G8878 (B2YGG2)
2.A.1.2.42









The multidrug efflux pump, EmrD-3 (exports ethidium, linezolid, tetraphenylphosphonium chloride, rifampin, erythromycin, minocycline, trimethoprim, chloramphenicol, and rhodamine) (Smith et al., 2009).

Bacteria
Proteobacteria
EmrD-3 of Vibrio cholerae (Q9KMQ3)
2.A.1.2.43









The multidrug efflux pump, Qdr3 (exports polyamines, quinidine, barban, cisplatin and bleomycin). The two halves of the protein each have an N-terminal. 150 residue hydrophilic region found in many fungi followed by a 200 residue, 6 TMS, transmembrane region. This suggests that an intragenic duplication event gave rise to 12 TMS proteins independently of most other MFS carriers, but this has not been demonstrated, possibly because of extensive sequence divergence of the second half.

Eukaryota
Fungi
Qdr3 of Saccharomyces cerevisiae (P38227)
2.A.1.2.44









Diglucosyl-diacylglycerol exporter or flippase, LtaA (lipoteichoic acid protein A) (Gründling and Schneewind, 2007)

Bacteria
Firmicutes
LtaA of Staphylococcus aureus (Q2FZP8)
2.A.1.2.45









The fructose-specific uniporter, Ffz1 (69% identical to Ffz2 
(2.A.1.2.46) and 66% identical to (2.A.1.2.23) (Leandro et al., 2011). 

Eukaryota
Fungi
Ffz1 of Zygosaccharomyces rouxii (C5E4Z7)
2.A.1.2.46









The fructose/glucose uniporter, Ffz2 (64% identical to 2.A.1.2.23). Both sugars are transported with similar affinities and efficiencies (Leandro et al., 2011). 

Eukaryota
Fungi
Ffz2 of Zygosaccharomyces rouxii (C5DX43)
2.A.1.2.47









The multidrug resistance efflux pump, HsMDR (YfmO2; Vardy et al., 2005).

Archaea
Euryarchaeota
HsMDR of Halobacterium sp. NRC-1 (Q9HS33)
2.A.1.2.48









tetracycline exporter

Eukaryota
Fungi
tetR exporter of Aspergillus niger (A2QTF4)
2.A.1.2.49









Putative tetracycline resistance protein

Archaea
Crenarchaeota
Putative tet resistance pump of Pyrobaculum aerophilum (Q8ZUX8)
2.A.1.2.50









MFS porter

Eukaryota
Dictyosteliida
MFS porter of Dictyostelium purpureum (F0ZU09)
2.A.1.2.51









Chloramphenicol (specific) resistance pump, CraA (43% identical to MdfA of E. coli) (Roca et al., 2009).

Bacteria
Proteobacteria
CraA of Acinetobacter baumannii (A3M9E9)
2.A.1.2.52









Puromycin resistance MDR protein, MdtM (Soo et al., 2011)

Bacteria
Proteobacteria
MdtM of E. coli (P39386)
2.A.1.2.53









MDR pump, SLC22A18 in lung cancer cells (Lei et al., 2012).

Eukaryota
Metazoa
SLC22A18 of Homo sapiens
2.A.1.2.54









LigA-like protein

Bacteria
Actinobacteria
LigA-like protein of Streptomyces coelicolor (Q9KYE9)
2.A.1.2.55









Peptide exporter (Ala-Gln and Ala-branched chain amino and dipeptides) (Hayashi et al., 2010).  May also export arabinose (but not xylose) and function as an MDRpump (Koita and Rao 2012).

Bacteria
Proteobacteria
YdeE of E. coli (P31126)
2.A.1.2.56









NCL7. Neuronal ceroid lipofuscinosis, a neuro-degenerative genetic disease, is caused by mutations in at least 8 different human genes, one of which, CLN7 (MFSD8), is associated with late infantile NCL. CLN7 is localized to lysosomes (Sharifi et al., 2010).

Eukaryota
Metazoa
NCL7 of Homo sapiens (Q8NHS3)
2.A.1.2.57









MFS-type transporter SLC18B1 (Solute carrier family 18 member B1)
Eukaryota
Metazoa
C6orf192 of Homo sapiens
2.A.1.2.58









Protein ZINC INDUCED FACILITATOR 1
Eukaryota
Viridiplantae
ZIF1 of Arabidopsis thaliana
2.A.1.2.59









Ucharacterized MFS-type transporter C330.07c; YJ87

Eukaryota
Fungi
YJ87 of Schizosaccharomyces pombe
2.A.1.2.60









YajR of 454 aas and 12 TMSs.  The 3-D structure in the outward-facing conformation is available at 3.15Å resolution, and the cytoplasmic C-terminal YAM domain has been solved to 1.07Å resolution.  This 65 aa YAM domain is thought to control the conformational states of the protein (Jiang et al. 2013; Jiang et al. 2014).

Bacteria
Proteobacteria
YajR of E. coli
2.A.1.2.61









SPX domain-containing membrane protein At1g63010

Eukaryota
Viridiplantae
At1g63010 of Arabidopsis thaliana
2.A.1.2.62









Putative MDR pump, YdhC.  Probably exports arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
YdhC of Escherichia coli
2.A.1.2.63









Probable drug/proton antiporter YHK8
Eukaryota
Fungi
YHK8 of Saccharomyces cerevisiae
2.A.1.2.64









Polyamine exporter 4 (Igarashi and Kashiwagi 2010).

Eukaryota
Fungi
TPO4 of Saccharomyces cerevisiae
2.A.1.2.65









Inner membrane transport protein YdhP

Bacteria
Proteobacteria
YdhP of Escherichia coli
2.A.1.2.66









Polyamine exporter 3 (Igarashi and Kashiwagi 2010).

Eukaryota
Fungi
TPO3 of Saccharomyces cerevisiae
2.A.1.2.67









Polyamine exporter 2 (Igarashi and Kashiwagi 2010).

Eukaryota
Fungi
TPO2 of Saccharomyces cerevisiae
2.A.1.2.68









Tetracycline resistance protein, class B (TetA(B)) (Metal-tetracycline/H+ antiporter).  Mutants defective in either transport or tetracycline binding have been isolated (Wright and Tate 2015).

Bacteria
Proteobacteria
TetA of Escherichia coli
2.A.1.2.69









Uncharacterized MFS-type transporter YttB

Bacteria
Firmicutes
YttB of Bacillus subtilis
2.A.1.2.70









Multidrug resistance protein 1 (Multidrug-efflux transporter 1)
Bacteria
Firmicutes
Bmr of Bacillus subtilis
2.A.1.2.71









Uncharacterized MFS-type transporter Rv2456c/MT2531
Bacteria
Actinobacteria
Rv2456c of Mycobacterium tuberculosis
2.A.1.2.72









Major facilitator superfamily domain-containing protein 9
Eukaryota
Metazoa
Mfsd9 of Mus musculus
2.A.1.2.73









Major facilitator superfamily domain-containing protein 10 (Tetracycline transporter-like protein)
Eukaryota
Metazoa
Mfsd10 of Mus musculus
2.A.1.2.74









Multidrug resistance protein MdtL
Bacteria
Proteobacteria
MdtL of Shewanella sp.
2.A.1.2.75









Tetracycline resistance protein, class E (TetA(E))
Bacteria
Proteobacteria
TetA of Escherichia coli
2.A.1.2.76









Major facilitator copper transporter 1, Mfc1.  Takes up copper in meiotic sporulating cells; present in the forespore membrane.  Induced under copper limitation.  Required for normal forespore development and spore copper-dependent amine oxidase activity (Beaudoin et al. 2011).

Eukaryota
Fungi
Mfc1 of Schizosaccharomyces pombe
2.A.1.2.77









CefT confers phenyacetate resistance (Fernández-Aguado et al. 2012).  It has been reported to be a hydrophilic beta-lactam transporter that is involved in the secretion of hydrophilic beta-lactams containing an α-aminoadipic acid side chain (isopenicillin N, penicillin N and deacetylcephalosporin C) (Cesareo et al. 2007; Ullán et al. 2002).

Eukaryota
Fungi
CefT of Acremonium chrysogenum
2.A.1.2.78









The PaaT (PenT) exporter.  PaaT is involved in penicillin production, possibly through the translocation of side-chain precursors (phenylacetate and phenoxyacetate) from the cytosol to the peroxisomal lumen across the peroxisomal membrane of P. chrysogenum.  It has a Pex19 (peroxisome biogenesis factor 19) binding sequence (residues 258 - 269) accounting for its peroxysomal location (Fernández-Aguado et al. 2012; Yang et al. 2012).

Eukaryota
Fungi
PaaT of Penicillum chysogenum (notatum)
2.A.1.2.79









The perylenequinone toxin, cercosporin, exporter, Ctb4

Eukaryota
Fungi
Ctb4 of Cercospora nicotianae
2.A.1.2.80









Putative permease of 458 aas

Eukaryota
Bangiophyceae
Putative permease of Galdieria sulphuraria
2.A.1.2.81









Uncharacterized MFS permease; encoded by a gene adjacent to one encoding a peroxiredoxin (an electron donor and antioxidant; Hanschmann et al. 2013).

Bacteria
Deinococcus-Thermus
UP of Deinococcus peraridilitoris
2.A.1.2.82









Uncharacterized MFS permease of 402 aas and 12 TMSs

Bacteria
Spirochaetes
UP of Leptospira interrogans
2.A.1.2.83









MmrA MFS protein. Homologous to drug exporter. RppA and MmrA are involved in amino acid uptake and efflux of antimicrobial agents including streptomycin, ethidium bromide and norfloxacin (Kimura et al. 2004).

Bacteria
Proteobacteria
MXAN_5906 of Myxococcus xanthus.  
2.A.1.2.84









Probable siderophore-specific exporter of 407 aas and 12 TMSs, MxcK.

Bacteria
Proteobacteria
MxcK of Stigmatella aurantiaca
2.A.1.2.85









Peeroxysomal phenylacetate/penoxyacetate transporter, PaaT (CefT) of 564 aas (Fernández-Aguado et al. 2013).

Eukaryota
Fungi
PaaT of Penicillium chrysogenum (Penicillium notatum)
2.A.1.2.86









Peroxisomal isopenicillin N importer, PenM (Evers et al. 2004; Fernández-Aguado et al. 2014).

Eukaryota
Fungi
PenM of Penicillium chrysogenum (Penicillium notatum)
2.A.1.2.87









Purine efflux porter of 392 aas, CepA.  Exports purine analogues, 6-mercaptopurine and 6-mercaptoguanine, but not to 2-aminopurine and purine nucleoside analogues. May show increased resistance to the antibiotics nalidixic acid and ampicillin.

Bacteria
Actinobacteria
CepA of Corynebacterium glutamicum
2.A.1.2.88









MFS porter of 442 aas

Archaea
Euryarchaeota
MFS porter of Pyrococcus furiosus
2.A.1.2.89









MFS porter of 454 aas

Bacteria
Actinobacteria
MFS porter of Streptomyces coelicolor
2.A.1.2.90









UMF4F of 405 aas and 12 TMSs

Bacteria
Firmicutes
UMF4F of Aectobacterium woodii
2.A.1.2.91









MFS permease of 554 aas and 12 TMSs

Eukaryota
Fungi
Putative MFS carrier of Metarhizium robertsii (Metarhizium anisopliae)
2.A.1.3:  The Drug:H+ Antiporter-2 (14 Spanner) (DHA2) Family
2.A.1.3.1









The main boron exporter in yeast, Atr1 (Kaya et al. 2009) (Aminotriazole, 4-nitroquinoline-N-oxide, etc.):H+ antiporter. Also exports L-cysteine (Yamada et al., 2006).

Eukaryota
Fungi
Atr1 of Saccharomyces cerevisiae
2.A.1.3.2









(CCCP, nalidixic acid, rhodamine 6G, methylviologen, deoxycholate, growth inhibitory steroid hormones (estradiol and progesterone) (Elkins and Mullis, 2006) SDS, organomercurials, etc.):H+ antiporter
Bacteria
Proteobacteria
EmrB of E. coli (P0AEJ0)
2.A.1.3.3









(Acriflavin, ethidium bromide, fluoroquinolones, etc.):H+ antiporter (Li et al. 2004; Rodrigues et al. 2011).

Bacteria
Actinobacteria
LfrA of Mycobacterium smegmatis
2.A.1.3.4









(Mono- and divalent organocation):H+ antiporter. Transmembrane helix 12 of QacA lines the bivalent cationic drug binding pocket (Hassan et al., 2007).

Bacteria
Firmicutes
QacA of Staphylococcus aureus (P0A0J9)
2.A.1.3.5









(Pristinamycin I and II, rifamycin, etc.):H+ antiporter
Bacteria
Actinobacteria
Ptr of Streptomyces pristinaespiralis
2.A.1.3.6









Me2+·tetracycline:2H+ or 2K+ antiporter
(the optimal Me2+ = Co2+) (Also transports Na+ or K+out in exchange for 2H+.)
Bacteria
Firmicutes
TetK of Staphylococcus aureus (P02983)
2.A.1.3.7









Actinorhodin:H+ antiporter, ActVa or ActA (Tahlan et al., 2007)
Bacteria
Actinobacteria
ActVa of Streptomyces coelicolor
2.A.1.3.8









Cephamycin:H+ antiporter
Bacteria
Actinobacteria
CmcT of Nocardia lactamdurans
2.A.1.3.9









Lincomycin:H+ antiporter
Bacteria
Actinobacteria
LmrA of Streptomyces lincolnensis
2.A.1.3.10









Methylenomycin:H+ antiporter
Bacteria
Firmicutes
MmrB of Bacillus subtilis
2.A.1.3.11









Puromycin:H+ antiporter
Bacteria
Actinobacteria
Pur8 of Streptomyces lipmanii
2.A.1.3.12









Tetracenomycin:H+ antiporter
Bacteria
Actinobacteria
TcmA of Streptomyces glaucescens
2.A.1.3.13









Unconjugated bile acid uptake transporter
Bacteria
Firmicutes
BaiG of Eubacterium sp. strain VPI 12708
2.A.1.3.14









Methylviologen (paraquat):H+ antiporter
(also exports ethidium bromide, acriflavin, malachite green, pyonine B and benzyl viologen)
Bacteria
Proteobacteria
SmvA of Salmonella typhimurium
2.A.1.3.15









Rifamycin:H+ antiporter
Bacteria
Actinobacteria
RifP of Amycolatopsis mediterranei
2.A.1.3.16









The Me2+·tetracycline:2H+ antiporter
(Me2+ = Co2+, Mg2+, Mn2+) (also probably
a Na+ or K+:2H+ antiporter) (Wang et al. 2000).

Bacteria
Firmicutes
TetA(L) of Bacillus subtilis
2.A.1.3.17









The trimethoprim-sensitivity protein, YebQ (increases sensitivity to trimethoprim)
Bacteria
Proteobacteria
YebQ of E. coli
2.A.1.3.18









Efflux pump for plant-bacterial signaling molecules, phytoalexins, flavenoids and salicylate as well as drugs, RmrB
Bacteria
Proteobacteria
RmrB of Rhizobium etli
2.A.1.3.19









Paraquot efflux pump, PqrB (Cho et al., 2003)
Bacteria
Actinobacteria
PqrB of Streptomyces coelicolor (AAG45950)
2.A.1.3.20









Long chain fatty acid efflux pump, FarB (Lee et al., 2003) (exports antimicrobial long chain fatty acids; functions with MFP auxillary protein, FarA (TC# 8.A.1.1.2)) (Lee et al., 2006)
Bacteria
Proteobacteria
FarB of Neisseria gonorrhoeae (AAD54074)
2.A.1.3.21









Siderophore, achromobactin efflux pump, YhcA (Franza et al., 2005)
Bacteria
Proteobacteria
YhcA of Erwinia (Pectobacterium) chrysanthemi (AAL14569)
2.A.1.3.22









The Tet38 tetracycline-resistance protein of Staphylococcus aureus (Truong-Bolduc et al., 2005)
Bacteria
Firmicutes
Tet38 of Staphylococcus aureus (AAV80464)
2.A.1.3.23









The NorB multidrug resistance pump (exports hydrophilic quinolones, ethidium bromide, cetrimide, sparfloxacin, moxifloxacin and tetracycline) (Truong-Bolduc et al., 2005)
Bacteria
Firmicutes
NorB of Staphylococcus aureus (BAB42529)
2.A.1.3.24









The VceAB multidrug (hydrophobic compounds including deoxycholate (DOC), antibiotics, such as chloramphenicol and nalidixic acid, and the proton motive force uncoupler, cyanide carbonyl m-chlorophenylhydrazone (CCCP)) resistance pump (functions with outer membrane VceC (TC#1.B.17.3.6) or OprM (2.A.6.2.21), an OMF family member; The C-terminal domain of the Pseudomonas aeruginosa OprM and the alpha-helical hairpin domain of Vibrio cholerae VceA play important roles in recognition/specificity/recruitment in the assembly of a functional, VceAB-OprM chimeric efflux pump (Bai et al., 2010).

Bacteria
Proteobacteria
VceAB of Vibrio cholerae
VceB (MFS), NP_231054
VceA (MFP), NP_231053
2.A.1.3.25









Actinorhodin (blue pigmented antibiiotic) transporter, ActII-2

Bacteria
Actinobacteria
ActII-2, Actinorhodin transporter of Streptomyces coelicolor (P46105).
2.A.1.3.26









Novobiocin/deoxycholate exporting MDR efflux pump, MdtD or YegB (Baranova and Nikaido, 2002).  Also exports arabinose but not xylose (Koita and Rao 2012). Regulated by the transcription factor, BaeR (Nagakubo et al. 2002).

Bacteria
Proteobacteria
YegB of E. coli (P36554)
2.A.1.3.27









The vacuolar basic amino acid (Arg, Lys, His) transporter, Vba3 (Shimazu et al., 2005)

Eukaryota
Fungi
Vba3 of Saccharomyces cerevisiae (P25594)
2.A.1.3.28









MDR multidrug efflux pump, EbrE (involved in colony growth, dependent on Ca2+, Mg2+, Na+ and K+) (Lee et al., 2007)
Bacteria
Actinobacteria
EbrE of Streptomyces lividans (Q939A4)
2.A.1.3.29









The metal:tetracycline/oxytetracycline resistance efflux pump, TctB (563 aas)
Bacteria
Actinobacteria
TctB of Streptomyces rimosus (O69070)
2.A.1.3.30









Lincomycin resistance protein; Lincomycin:H+ antiporter, LmrB
Bacteria
Firmicutes
LmrB of Bacillus subtilis (O35018)
2.A.1.3.31









The hydrophilic fluroquinolones efflux pump, QepA (Perichon et al., 2008). Exports hydrophilic quinolones, norfloxacin, and ciprofloxacin.

Bacteria
Proteobacteria
QepA of E. coli (A5H8A5)
2.A.1.3.32









Landomycin A efflux pump, LanJ (Otash et al., 2008)
Bacteria
Actinobacteria
LanJ of Streptomyces cyanogenus (Q9ZGB6)
2.A.1.3.33









Multidrug (including novobiocin, streptomycin, and actinomycin D) resistance porter, MdtP (YusP)
Bacteria
Firmicutes
MdtP of Bacillus subtilis (O32182)
2.A.1.3.34









The P55 drug efflux pump (Rv141Oc) (extrudes drugs including rifampicin and clifazimine, first- and second-line anti-tuberculosis drugs. CCCP and valinomycin inhibited drug resistance) (Ramón-García et al., 2009).  P55 also exports malachite green, ethidium bromide, isoniazid and ethambutol (Bianco et al. 2011).  Functions together with the outer membrane lipoprotein porin, LprG, also called P27 and Lpp-27 (Bianco et al. 2011; Farrow and Rubin 2008).  Required together with LprG for normal colony morphology and sliding motility, possibly due to alterred cell wall composition (Farrow and Rubin 2008).  Required together with LprG for normal colony morphology and sliding motility, possibly due to alterred cell wall composition (Farrow and Rubin 2008).

Bacteria
Actinobacteria
P55 drug efflux pump of Mycobacterium tuberculosis (P71678)
2.A.1.3.35









The 14 TMS FmtC (MrpF; MprF) protein of 840 aas, involved in methecillin and daptomycin resistance. Residues 1-550 comprise a 14TMS MFS permease domain while residues 551-840 comprise a "phosphatidylglycerol lysyl transferase" (or synthetase) domain (DUF2156), also called "lysyl cardiolipid synthase". FmtC may be distantly related to lysyl-tRNA synthetases. Similar to 2.A.1.3.44 in all these respects.  Ernst et al. 2015 have reported that TMSs 1-6 of FmtC of S. aureus is a flippase for lysylinated phosphatidyl glycerol, and that the entire system is a dimer.

Bacteria
Firmicutes
FmtC of Staphylococcus aureus (D1QCY9)
2.A.1.3.36









EmrKY-TolC MDR efflux pump. (also exports cysteine (Yamada et al., 2006)) (similar to 2.A.1.3.2)

Bacteria
Proteobacteria
EmrKY-TolC of E. coli
EmrK (MFP) (C5W790)
EmrY (MFS) (C5W789)
2.A.1.3.37









The uridine/deoxyuridine/5-fluorouridine uptake transporter, UriP (llmg_0856) (480aas; 14TMSs) (Martinussen et al., 2010)

Bacteria
Firmicutes
UriP of Lactococcus lactis (A2RJJ9)
2.A.1.3.38









MFS porter of unknown function

Bacteria
Actinobacteria
MFS porter of Streptomyces viridochromogenes (D9X7X8)
2.A.1.3.39









The antimicrobial efflux pump, LmrS. Exports linezolid and tetraphenylphosphonium chloride (TPCL) > sodium dodecyl sulfate (SDS), trimethoprim, and chloramphenicol. (most similar to LmrB (2.A.1.3.30)) (Floyd et al., 2010).

Bacteria
Firmicutes
LmrS of Staphylococcus aureus (Q5HE38)
2.A.1.3.40









The phenazine resistance pump. Also exports D-alanyl-griseoluteic acid; possibly in conjunction with a chaperone protein, EhpR. The crystal structure of EhpR is known (Yu et al., 2011). Note: Phenazines are toxic redox active secondary metabolites that many bacteria secrete.

Bacteria
Proteobacteria
EhpJ of Panloea (Enterobacter) agglomerans (O32600)
2.A.1.3.41









Rv0585c; 795aas: 1 - 220aas, TMSs 1-6; 221-490aas, kinase domain; 491-795, TMS: 7-14. The C-terminal 8 TMS hydrophobic domain is homologous to an N-terminal domain in fused Mg2+-ATPases (3.A.3.4.3 and 3.A.3.4.4) and members of family 9.B.3.

Bacteria
Actinobacteria
Rv0585c of Mycobacterium tuberculosis (O53781)
2.A.1.3.42









Putative oxacillin resistance-associated protein, FmtC (872 aas; 14 N-terminal TMSs (residues 1-530) plus a largely hydrophilic DUF2156 domain (residues 531-872). Similar throughout its length to FmtC of Staphylococcus aureus (2.A.1.3.37). Residues 67-326 (TMSs 2-8) are homologous to residues 527-786 (TMSs 8-14) in Rv0585c of Mycobacterium tuberculosis (2.A.1.3.43). Residues 6-314 are also homologous  to an extra hydrophobic domain in Mg2+ P-type ATPases  (3.A.3.4.3 and 3.A.3.4.4). The C-terminal domain belongs to the DUF2156 superfamily. Homologues of the hydrophilic domain retrieved with NCBI BLAST searches are annotated as "putative" lysylphosphatidyl-glycerol synthetase. Some include full length MFS fusion proteins.

Bacteria
Proteobacteria
FmtC of Brucella melitensis (D1F3T8)
2.A.1.3.43









MFS efflux pump, AmvA (AedF). Mediates drug, dye, detergent, antibiotic and disinfectant resistance (Rajamohan et al., 2010; Hassan et al. 2011). 98.6% identical to AdeF (2.A.1.3.46).

Bacteria
Proteobacteria
AmvA of Acinetobacter baumannii (C4PAW9)
2.A.1.3.44









MDR pump, AdeF (AmvA) exports ethidium, DAPI, and chlorhexidine (Hassan et al. 2011). 98.6% identical to AmvA (2.A.1.3.45).

Bacteria
Proteobacteria
AdeF of Acinetobacter baumannii (A3M6E0)
2.A.1.3.45









Putative MFS permease TMSs 10-13 (shows limited sequence similarity with TMSs 2-5 in 9.B.111.1.1 and 9.B.111.1.2).

Bacteria
Proteobacteria
MFS permease of Bilophila wadsworthia (E5Y3Y1)
2.A.1.3.46









The phenicol (florfenicol/chloramphenicol) exporter, FexB (Liu et al., 2012)

Bacteria
Firmicutes
FexB of Enterococcus faecium (G9FS16)
2.A.1.3.47









The trichothecene efflux pump, TRI12 (Alexander et al., 1999; Wuchiyama et al., 2000). See also Fang et al. (2012).

Eukaryota
Fungi
TRI12 of Fusarium sporotrichioides (Q9C1B3)
2.A.1.3.48









Probable multidrug-efflux transporter Rv1634/MT1670

Bacteria
Actinobacteria
Rv1634 of Mycobacterium tuberculosis
2.A.1.3.49









Multidrug resistance protein Stp (Spectinomycin tetracycline efflux pump)

Bacteria
Actinobacteria
Stp of Myconbacterium tuberculosis
2.A.1.3.50









Multidrug resistance protein 3 (Multidrug-efflux transporter 3)
Bacteria
Firmicutes
Bmr3 of Bacillus subtilis
2.A.1.3.51









Probable transport protein HsrA (High-copy suppressor of RspA)
Bacteria
Proteobacteria
HsrA of Escherichia coli
2.A.1.3.52









Drug resistance protein YOR378W.  Does not export boron (Bozdag et al. 2011).

Eukaryota
Fungi
YOR378W of Saccharomyces cerevisiae
2.A.1.3.53









Azole resistance protein 1
Eukaryota
Fungi
AZR1 of Saccharomyces cerevisiae
2.A.1.3.54









Protein SGE1 (10-N-nonyl acridine orange resistance protein) (Crystal violet resistance protein)
Eukaryota
Fungi
SGE1 of Saccharomyces cerevisiae
2.A.1.3.55









Uncharacterized MFS-type transporter YubD

Bacteria
Firmicutes
YubD of Bacillus subtilis
2.A.1.3.56









Uncharacterized MFS-type transporter YvmA

Bacteria
Firmicutes
yvmA of Bacillus subtilis
2.A.1.3.57









Uncharacterized MFS-type transporter YwoD

Bacteria
Firmicutes
YwoD of Bacillus subtilis
2.A.1.3.58









Uncharacterized MFS-type transporter YfiU

Bacteria
Firmicutes
YfiU of Bacillus subtilis
2.A.1.3.59









MDR efflux pump, NorC (Truong-Bolduc et al. 2006).

Bacteria
Firmicutes
NorC of Staphylococcus aureus
2.A.1.3.60









MDR efflux pump, SdrM.  Exports norfloxacin, acriflavin and ethidium bromide (Yamada et al. 2006).

Bacteria
Firmicutes
SdrM of Staphylococcus aureus
2.A.1.3.61









MDR efflux pump, MdeA.  Exports hoechst 33342, doxorubicin, daunorubicin, tetraphenyl phosphonium, ethidium bromide and rhodamine 6G (Yamada et al. 2006).

Bacteria
Firmicutes
MdeA of Staphylococcus aureus
2.A.1.3.62









MDR efflux pump, AedC (Hassan et al. 2011).  Shown to export chloramphenicol and tetracycline.

Bacteria
Proteobacteria
AedC of Acinetobacter baumannii
2.A.1.3.63









Iron homeostasis protein, AedD; may function in siderophore export (Hassan et al. 2011).

Bacteria
Proteobacteria
AedD of Acinetobacter baumannii
2.A.1.3.64









Uptake permease for cholate (steroid) metabolites, CamM of 513 aas and 14 TMSs.  Uptake of 3,7(R),12(S)-trihydroxy-9-oxo-9,10-seco-23,24-bisnorchola-1,3,5(10)-trien-22-oate was observed (Swain et al. 2012).

Bacteria
Actinobacteria
CamM of Rhodococcus jostii
2.A.1.3.65









ThMFS1 of 563 aas and 14 TMSs.  Catalyzes export of fungicides causing tolerance.  May export trichodermin, but if so, it is not the only exporter of this secondary metabolite (Liu et al. 2012).

Eukaryota
Fungi
MFS1 of Trichoderma harzianum (Hypocrea lixii)
2.A.1.3.66









MFS permease of 413 aas and 12 tMSs

Bacteria
Proteobacteria
MFS permease of Pseudomonas aeruginosa
2.A.1.3.67









MFS porter of 462 aas and 14 TMSs

Bacteria
Deinococcus-Thermus
MFS porter of Deinococcus radiodurans
2.A.1.3.68









The PfMFS transporter (551 aas; 14 putative TMSs) is involved in the acid resistance and
intracellular pH homeostasis of Penicillium funiculosum (Xu et al. 2014). This protein was
not in UniProt, and its closest orthologue, PmMFS of Penicillium marneffei, is therefore
presented here.
Eukaryota
Fungi
PfMFS of Talaromyces (Penicillium) funiculosum
2.A.1.3.69









Drug resistance pump, YMR279c of 540 aas.  When overexpressed, confers boron resistance, but is not induced by boron (Bozdag et al. 2011). 

Eukaryota
Fungi
YMR279c of Saccharomyces cerevisiae (Baker's yeast)
2.A.1.4:  The Organophosphate:Pi Antiporter (OPA) Family
2.A.1.4.1









Sugar-P:Pi antiporter (transports many sugar-phosphates - both 1- and 6-P esters)
Bacteria
Proteobacteria
UhpT of E. coli (P0AGC0)
2.A.1.4.2









P-glycerate:Pi antiporter, Pgt.  Takes up phosphoenolpyruvate, 2-phosphoglycerate, and 3-phosphoglycerate as sole sources of carbon and energy for rapid growth (Saier et al. 1975).  Not present in E. coli K12, but is present in many intracellular pathogenic strains of E. coli (Tang and Saier, unpublished observations).

Bacteria
Proteobacteria
PgtP of Salmonella typhimurium
2.A.1.4.3









Glycerol-P:Pi antiporter (may function by a 'rocker switch' mechanism; Law et al., 2007). The 3-d structure is known (3.3Å resolution) (Huang et al., 2003; Lemieux et al., 2005; Lemieux, 2007).

Bacteria
Proteobacteria
GlpT of E. coli
2.A.1.4.4









Hexose-P:Pi antiporter regulatory protein; senses external glucose-6-P and transports it with high affinity and low efficiency
Bacteria
Proteobacteria
UhpC of E. coli
2.A.1.4.5









Microsomal (ER/Golgi) glucose-6-P:Pi antiporter (glycogen storage disease (GSD1b and 1c); Gierke''s disease protein) (SLC37A2 in mice, associated with white adipose tissue obesity and expressed at high levels in macrophage) (4 isoforms present in humans (Chen et al., 2008)).  SLC37A1 and A2 can not substitute for A4.  91 mutations have been observed in human patients (Chou and Mansfield 2014).  Inhibited by cholorogenic acid although SLC37A1 and A2 are not.  SLC37A3 had not been characterized by 2014 (Chou and Mansfield 2014).

Eukaryota
Metazoa
SLC37A4 of Homo sapiens
2.A.1.4.6









Glucose-6-P:Pi antiporter, Hpt (may also transport other organophosphates including C3 organophosphates).
Bacteria
Chlamydiae/Verrucomicrobia group
Hpt of Chlamydia pneumoniae (spQ9Z7N9 & gi9979188) & pirA72050
2.A.1.4.7









Putative glycerol-3-phosphate (G-3-P) transporter, G3PP (most similar to TC# 2.A.1.4.6, 22% identity).  Has been shown to catalyze glucose 6-P:Pi antiport across the endoplasmic reticular membrane(Pan et al. 2011).

Eukaryota
Metazoa
SLC37A1 of Homo sapiens
2.A.1.4.8









solute carrier family 37 (putative glycerol-3-phosphate transporter), member 2.  Has been shown to catalyze glucose 6-P:Pi antiport across the endoplasmic reticular membrane (Pan et al. 2011).

Eukaryota
Metazoa
SLC37A2 of Homo sapiens
2.A.1.4.9









solute carrier family 37 (glycerol-3-phosphate transporter), member 3
Eukaryota
Metazoa
SLC37A3 of Homo sapiens
2.A.1.4.10









2-phosphonoacetate/2-phosponoproprionate uptake porter of 428 aas, PhnB.  The PhnA protein is a hydrolase, and PhnC is a positive transcriptional regulator.  Induction occurs with either of the two substrates (Kulakova et al. 2001).

Bacteria
Proteobacteria
PhnB of Pseudomonas fluorescens
2.A.1.4.11









Glycerol-3-phosphate:inorganic phosphate antiporter, GlpT (Frohlich and Audia 2013).

Bacteria
Proteobacteria
GlpT of Rickettsia prowazekii
2.A.1.5:  The Oligosaccharide:H+ Symporter (OHS) Family
2.A.1.5.1









Lactose:H+ symporter, LacY. Transports lactose, melibiose and TMG. Crystal structures and modeling reveal the cytoplasmic open state and the periplasmic open state (PDB ID: 1PV7; Abramson et al., 2003Pendse et al., 2010). The membrane lipid composition determines the topology of LacY (Dowhan and Bogdanov, 2011). Smirnova et al. (2011) have provided evidence that the opening of the periplasmic cavity in LacY is the limiting step for sugar binding. Evidence for an alternating sites mechanism of transport has been summarized (Smirnova et al., 2011). Eames and Kortemme (2012) have shown that when considering expression of the lac operon, LacY function (H+ transport) and not protein production is the primary origin of cost fitness. Homology threading of several MFS porters based on the LacY 3-d structure has been reported (Kasho et al., 2006). The alternating-access mechanism has been suggested to arise from inverted topological repeats (Radestock and Forrest, 2011; Madej et al. 2012), but this proposal has been contested (Västermark and Saier 2014; Västermark et al. 2014). Mechanistic features of LacY have been summarized (Kaback 2015). 

Bacteria
Proteobacteria
LacY of E. coli
2.A.1.5.2









Raffinose:H+ symporter, RafB, can be mutated to transport maltose (Van Camp et al., 2007).

Bacteria
Proteobacteria
RafB of E. coli
2.A.1.5.3









Sucrose:H+ symporter, CscB, also transports maltose (Peng et al. 2009).
Bacteria
Proteobacteria
CscB of E. coli
2.A.1.5.4









Melibiose:H+ symporter, MelY (Shinnick et al., 2003). Transports melibiose and lactose, but not TMG (Tavoulari and Frillingos, 2007)
Bacteria
Proteobacteria
MelY of Enterobacter cloacae
2.A.1.6:  The Metabolite:H+ Symporter (MHS) Family
2.A.1.6.1









Citrate:H+ symporter
Bacteria
Proteobacteria
CitA of Klebsiella pneumoniae
2.A.1.6.2









α-Ketoglutarate (oxoglutarate):H+ symporter (Seol and Shatkin 1992; Seol and Shatkin 1992).  May also export arabinose but not xylose (Seol and Shatkin 1992).  May also export arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
KgtP of E. coli (P0AEX3)
2.A.1.6.3









Dicarboxylate:H+ symporter
Bacteria
Proteobacteria
PcaT of Pseudomonas putida
2.A.1.6.4









(Proline/glycine-betaine):(H+/Na+) symporter, ProP (also transports taurine, ectoine, pipecolate, proline-betaine, N,N-dimethylglycine, carnitine, and 1-carboxymethyl-pyridinium) (subject to osmotic activation). Transmembrane helix I and periplasmic loop 1 are involved in osmosensing and osmoprotectant transport (Keates et al., 2010).

Bacteria
Proteobacteria
ProP of E. coli (P0C0L7)
2.A.1.6.5









4-Methyl-o-phthalate:H+ symporter
Bacteria
Proteobacteria
MopB of Burkholderia cepacia
2.A.1.6.6









Shikimate:H+ symporter
Bacteria
Proteobacteria
ShiA of E. coli
2.A.1.6.7









The citrate/tricarballylate:H+ symporter (CitA or TcuC); probably orthologous to 2.A.1.6.1 (Lewis et al., 2004)
Bacteria
Proteobacteria
TcuC of Salmonella enterica serovar Typhimurium LT2 (P0A2G3)
2.A.1.6.8









The acetate/monochloroacetate (haloacid) permease, Deh4p (Km = 5.5 mμM for acetate; 9 mμM for monochloroacetate) (Yu et al., 2007; Su and Tsang 2012).

Bacteria
Proteobacteria
Deh4 of Burkholderia cepacia or sp. MBA4 (Q7X4L6)
2.A.1.6.9









YdfJ. Can function as an inward rectifying K+ channel when expressed in animal cells as measured by whole cell patch clamping. Blocked by barium and protopine (Tang et al., 2011).

Bacteria
Proteobacteria
YdfJ of E. coli (P77228)
2.A.1.6.10









Inner membrane metabolite transport protein YhjE

Bacteria
Proteobacteria
YhjE of Escherichia coli
2.A.1.6.11









Acetate/haloacid transporter, Dehp2, with a possible atypical topology (Tse et al. 2009).  Transports acetate, chloroacetate, bromoacetate, 2-chloropropionate, and possibly, with low affinity, glycolate, lactate and pyruvate (based on weak inhibition results).  Inducible by chloroacetate (Su and Tsang 2012).  This protein is 79% identical to its paralogue, Deh4p (TC# 2.A.1.6.8) which differs in that it shows lower apparent affinity for 2-chloropropionate.

Bacteria
Proteobacteria
Dehp2 of Burkholderia caribensis (formerly sp. MBA4)
2.A.1.6.12









The putative thiazole transporter, ThiU. Regulatyed by TPP riboswitch (Rodionov et al. 2002)

Bacteria
Proteobacteria
ThiU of Haemophilus influenzae (P44699)
2.A.1.7:  The Fucose: H+ Symporter (FHS) Family
2.A.1.7.1









L-Fucose:H+ symporter. The x-ray structure (3.1Å resolution) with an outward open, amphipathic cavity has been solved. Asp46 and Glu135 can undergo cycles of protonation (Dang et al., 2010). 

Bacteria
Proteobacteria
FucP of E. coli
2.A.1.7.2









Glucose/galactose porter
Bacteria
Proteobacteria
Ggp of Brucella abortus (P0C105)
2.A.1.7.3









Glucose/Mannose/Xylose: H+ symporter (Paulsen et al., 1998; G.Gosset, personal communication).

Bacteria
Firmicutes
GlcP of Bacillus subtilis
2.A.1.7.4









Rat kidney Na+-dependent glucose (methyl α-glucoside) transporter, NaGLT1 (glucose:Na+:Na+=1:1) (Horiba et al., 2003)
Eukaryota
Metazoa
NaGLT1 of Rattus norvegicus (BAC57446)
2.A.1.7.5









2-Deoxy-D-ribose porter, DeoP (Christensen et al., 2003).  Plays a role in colonization of the mouse intestine (Martinez-Jéhanne et al. 2009).

Bacteria
Proteobacteria
DeoP of Salmonella typhimurium LT-2 (gi 16767076)
2.A.1.7.6









Sucrose permease, ScrT (Rodionov et al., 2010)

Bacteria
Proteobacteria
ScrT of Shewanella frigidimarina (ABI73814)
2.A.1.7.7









The Na+-dependent sugar transporter, HP1174 (transports glucose, galactose, mannose and 2-deoxyglucose (Psakis et al. 2009)). (most similar to 2.A.1.7.2; 49% identity)
Bacteria
Proteobacteria
HP1174 of Helicobacter pylori (O25788)
2.A.1.7.8









N-acetylglucosamine porter, NagP (Rodionov et al. 2010).

Bacteria
Proteobacteria
NagP of Shewanella oneidensis (Q8EBL0)
2.A.1.7.9









The putative N-acetylgalactosamine porter, AgaP (Leyn et al. 2012).

Bacteria
Proteobacteria
AgaP of Shewanella amazonensis (A1S4V0)
2.A.1.7.10









The putative glucose porter, GlcP (Rodionov et al., 2010).

Bacteria
Proteobacteria
GlcP of Shewanella amazonensis (A1S5F4)
2.A.1.7.11









The putative mannose porter, ManPl (Rodionov et al., 2010).

Bacteria
Proteobacteria
ManPl of Shewanella amazonensis (A1S297)
2.A.1.7.12









The putative trehalose porter, TreT (Rodionov et al., 2010)

Bacteria
Proteobacteria
TreT of Shewanella frigidimarina (Q07XD1)
2.A.1.7.13









Bypass of stop codon protein 6
Eukaryota
Fungi
BSC6 of Saccharomyces cerevisiae S288c
2.A.1.7.14









Protein TsgA

Bacteria
Proteobacteria
TgsA of E. coli
2.A.1.7.15









Major facilitator superfamily domain-containing protein 4-A
Eukaryota
Metazoa
Mfsd4a of Danio rerio
2.A.1.7.16









The putative mannose porter, ManP (Rodionov D.A., personal communication).
Regulated by mannose regulon ManR.

Bacteria
Bacteroidetes/Chlorobi group
ManP (Q8A5Y0) of Bacteroides thetaiotaomicron
2.A.1.7.17









The putative fructose porter, FruP (Rodionov D.A., personal communication).
Regulated by fructose oligosaccharide utilization regulon.

Bacteria
Bacteroidetes/Chlorobi group
FruP (Q8A6W8) of Bacteroides thetaiotaomicron
2.A.1.7.18









The putative N-acetylglucosamine porter, NagP (Rodionov D.A., personal communication).
Regulated by heparin utilization regulon.

Bacteria
Bacteroidetes/Chlorobi group
NagP (Q89YS8) of Bacteroides thetaiotaomicron
2.A.1.7.19









Probable glucose transporter encoded by a gene sandwiched in between two genes encoding a glucose 1-dehydrogenase and a gluconolactonase.

Bacteria
Chlamydiae/Verrucomicrobia group
Glucose permease of Parachlamydia acanthamoebae
2.A.1.8:  The Nitrate/Nitrite Porter (NNP) family
2.A.1.8.1









Nitrate/H+ symporter (K1);Nitrate/nitrite antiporter (K2).  The 3-d structure is available revealing a positively charged pathway for nitrate/nitrite lined with arginine residues with no apparent proton pathway suggesting exchange transport is the primary or sole mechanism.  The pathway is between the two halves of the protein and a rocker switch mechanism was proposed (Zheng et al. 2013).

Bacteria
Proteobacteria
NarK (NarK1-K2) of E. coli
2.A.1.8.2









Nitrate uptake porter
Bacteria
Firmicutes
NasA of Bacillus subtilis
2.A.1.8.3









Nitrate/nitrite uptake porter
Bacteria
Cyanobacteria
NrtP of Synechococcus PCC7002
2.A.1.8.4









Nitrate transporter
Eukaryota
Bacillariophyta
Nitrate porter of Cylindrotheca fusiformis
2.A.1.8.5









Nitrate/nitrite transporter/antiporter, CrnA/NrtA (Unkles et al., 1991; Beckham et al. 2010). The nitrate signature sequences (NS1 and NS2) in TMSs 5 and 11 and arg residues in TMSs 2 and 8 may influence substrate binding (Unkles et al., 2012).

Eukaryota
Fungi
CrnA of Emericella nidulans
2.A.1.8.6









Nitrate transporter
Eukaryota
Viridiplantae
Nitrate porter of Chlamydomonas reinhardtii
2.A.1.8.7









High affinity Nitrate/nitrite uptake transporter, Nar4.

Eukaryota
Viridiplantae
Nar4 of Chlamydomonas reinhardtii (A8J4P3) 
2.A.1.8.8









NO2- extrusion, NO3-/NO2- exchange permease, NarK1
Bacteria
Deinococcus-Thermus
NarK1 of Thermus thermophilus HB8
2.A.1.8.9









NO2- extrusion, NO3-/NO2- exchange permease, NarK2
Bacteria
Deinococcus-Thermus
NarK2 of Thermus thermophilus HB8
2.A.1.8.10









NO3-/NO2- transporter (NO3- uptake permease; NO2- exporter) (probable NO3-/NO2- antiporter) (stress-induced; Clegg et al., 2006; Jia et al. 2009)

Bacteria
Proteobacteria
NarU of E. coli
2.A.1.8.11









The 24 TMS, 2 domain, NarK1-NarK2 porter (NarK1 = a NO3-/H+ symporter; NarK2 = a NO3-/NO2- antiporter).  NarK1 is a nitrate/proton symporter with high affinity for nitrate while NarK2 is a nitrate/nitrite antiporter with lower affinity for nitrate (Goddard et al., 2008).  Each transporter requires two conserved arginine residues for activity.  A transporter consisting of inactivated NarK1 fused to active NarK2 has a dramatically increased affinity for nitrate compared with NarK2 alone, implying a functional interaction between the two domains (Goddard et al., 2008).
Bacteria
Proteobacteria
NarK1/NarK2 of Roseobacter denitrificans (Q166T6)
2.A.1.8.12









The root cortical and epidermal cell, high affinity, plasma membrane, NO3- uptake transporter, NRT2.1 (Wirth et al., 2007). Also functions in nitrate sensing and signaling (Miller et al., 2007; Girin et al., 2010). Activity only occurs when NRT2.1 is complexed with NAR2.1 (WR3; 8.A.20.1.1) in a 2:2 tetrameric complex (Yong et al., 2010). NAR2.1 has an N-terminal and a C-terminal TMS and has been annotated as a calcineurin-like phosphoesterase family member (Yong et al., 2010).  Ntr transporters may also play a role in gaseous NO2 uptake by leaves (Hu et al. 2014).  The Medicago truncatula ortholog has been characterized (Pellizzaro et al. 2014).

Eukaryota
Viridiplantae
NRT2.1 of Arabidopsis thaliana (O82811)
2.A.1.8.13









High affinity nitrate/nitrite antiporter and uptake porter, NrtB (Unkles et al., 1991; 2011; Wang et al. 2008).

Eukaryota
Fungi
NrtB of Emericella (Aspergillus) nidulans (Q8X193)
2.A.1.8.14









Nitrate/nitrite uptake porter, NapA (Wang et al., 2000)

Bacteria
Cyanobacteria
NapA of Trichodesmium sp. WH 9601 (Q9RA38)
2.A.1.8.15









Probable nitrate transporter NarT

Bacteria
Firmicutes
NarT of Staphylococcus carnosus
2.A.1.8.16









MFS porter of 430 aas

Bacteria
Proteobacteria
MFS porter of Rhizobium loti
2.A.1.9:  The Phosphate: H+ Symporter (PHS) Family
2.A.1.9.1









High affinity Pi uptake porter (also functions in Mn2+ homeostasis); may transport a phosphate · Mn2+ complex (Jensen et al., 2003). Also takes up selenite (Lazard et al., 2010).

 

Eukaryota
Fungi
Pho84 of Saccharomyces cerevisiae (P25297)
2.A.1.9.2









Pi uptake porter, Pho84

Eukaryota
Fungi
Pho-84 of Neurospora crassa (Q7RVX9)
2.A.1.9.3









Pi uptake porter. Four close paralogues in Medicago truncatula (PT1-4), all localized to roots, show differing affinities for phosphate (Liu et al. 2008).
Eukaryota
Viridiplantae
PT1 of Solanum tuberosum
2.A.1.9.4









Pht1;2(1;4) (PT2), a low affinity Pi uptake transporter, functioning throughout the plant (Ai et al., 2009) (76% identical to 2.A.1.9.3).

Eukaryota
Viridiplantae
Pht1;2(1;4) of Oryza sativa (Q01MW8)
2.A.1.9.5









Pht1;6 (PT6), a high affinity Pi uptake transporter, functioning thoughout the plant (Ai et al., 2009) (75% identical to 2.A.1.9.3)

Eukaryota
Viridiplantae
Pht1;6 (PT6) of Oryza sativa (Q8H6H0)
2.A.1.9.6









Phosphate transporter-5, PT5. Catalyzes phosphate:H+ symport (Liu et al., 2008).

Eukaryota
Viridiplantae
PT5 of Medicago truncatula (A5H2U6)
2.A.1.9.7









Organic phosphate (glycerophosphoinositol and glycerophosphocholine, the products of phospholipase-B mediated deacylation of phosphatidylinositol and phosphatidylcholine, respectively) transport protein GIT1 (Almaguer et al. 2006).

Eukaryota
Fungi
GIT1 of Saccharomyces cerevisiae
2.A.1.9.8









Putative inorganic phosphate transporter C23D3.12
Eukaryota
Fungi
SPAC23D3.12 of Schizosaccharomyces pombe
2.A.1.9.9









Inorganic phosphate transporter 1-1 (AtPht1;1) (H(+)/Pi cotransporter).  A Brassica napus homologue, Pht1;4, catalyzes phosphate uptake and affects root architecture (Ren et al. 2014).

Eukaryota
Viridiplantae
PHT1-1 of Arabidopsis thaliana
2.A.1.9.10









High affinity (25 mμM) phosphate uptake porter, PiPT (Yadav et al. 2010).  The high resolution structure has been determined by x-ray crystallography (Pedersen et al. 2013).

Eukaryota
Fungi
PiPT of Piriformospora indica
2.A.1.9.11









Phosphate transporter, PT, of 543 aas and 12 TMSs. It has a micormolar Km for phosphate uptake, is found in the plasma membrane and is induced by low medium phosphate concentrations (Wang et al. 2014).

Eukaryota
Fungi
PT in the ectomycorrhizal fungus, Boletus edulis
2.A.1.10:  The Nucleoside: H+ Symporter (NHS) Family
2.A.1.10.1









Nucleoside porter, NupG.  Guanosine, inosine, cytidine and thymidine but not uridine, adenosine and xanthosine are transported (Patching et al. 2005).

Bacteria
Proteobacteria
NupG of E. coli (P0AFF4)
2.A.1.10.2









Xanthosine porter, XapB.  Xanthosine, inosine, adenosine, cytidine and thymidine but not guanosine and uridine are transported (Seeger et al. 1995; Nørholm and Dandanell 2001Nørholm and Dandanell 2001).

Bacteria
Proteobacteria
XapB of E. coli
2.A.1.10.3









Dol-P-Glc:Glc(2)Man(9)GlcNAc(2)-PP-Dol alpha-1,2-glucosyltransferase (EC 2.4.1.256) (Alpha-1,2-glucosyltransferase ALG10-A) (Alpha-2-glucosyltransferase ALG10) (Asparagine-linked glycosylation protein 10) (Dolichyl-phosphoglucose-dependent glucosyltransferase ALG10)
Eukaryota
Fungi
DIE2 of Saccharomyces cerevisiae
2.A.1.10.4









Putative nucleoside transporter YegT

Bacteria
Proteobacteria
yegT of Escherichia coli
2.A.1.11:  The Oxalate:Formate Antiporter (OFA) Family
2.A.1.11.1









The oxalate:formate antiporter
Bacteria
Proteobacteria
OxlT of Oxalobacter formigenes
2.A.1.11.2









Putative MFS transporter of 399 aas; 12 TMSs.

Bacteria
Proteobacteria
MFS porter of Pseudomonas aeruginosa (Q9I458)
2.A.1.11.3









Inner membrane protein yhjX.  Regulated by Crp as well as the LytS-like histidine sensor kinase, YehU, and the corresponding LytTR-like response regulator, YehT.  Possibly induced by peptides as cells enter the stationary growth phase.  Forms a complex with the csiA transporter, YjiY (TC# 2.A.114.1.9) and two sensor kinase/response regulator pairs, YehU/YehT and YdpA/YdpB (Behr et al. 2014).  The carbon storage regulator A (CsrA) is involved in posttranscriptional regulation of both yjiY and yhjX (Behr et al. 2014).

Bacteria
Proteobacteria
yhjX of Escherichia coli
2.A.1.11.4









Uncharacterized membrane protein YJL163C
Eukaryota
Fungi
YJL163C of Saccharomyces cerevisiae
2.A.1.11.5









MFS-type transporter YcxA (ORF5) of 408 aas and 12 TMSs.  Capable of exporting the peptide antibiotic, surfactin, synthsized by a non-ribosome mechanism in B. subtilis (Li et al. 2015).

Bacteria
Firmicutes
YcxA of Bacillus subtilis
2.A.1.11.6









Uncharacterized MFS-type transporter YbfB

Bacteria
Firmicutes
YbfB of Bacillus subtilis
2.A.1.11.7









Uncharacterized protein of 512 aas and 12 TMSs.

Eukaryota
Florideophyceae
UP of Chondrus crispus
2.A.1.11.8









Uncharacterized protein of 404 aas

Bacteria
Proteobacteria
UP of Pseudomonas aeruginosa
2.A.1.12:  The Sialate:H+ Symporter (SHS) Family
2.A.1.12.1









The sialic acid porter, NanT.  N-acetylneuraminic acid (Neu5Ac) serves as a sole source of carbon and nitrogen for E. coli.  It is a mucus-derived carbon source in the mammalian gut. NanT can also take up and allow efficient growth on the related sialic acids, N-glycolylneuraminic acid (Neu5Gc) and 3-keto-3-deoxy-d-glycero-d-galactonononic acid (KDN) (Hopkins et al. 2013).

Bacteria
Proteobacteria
NanT of E. coli
2.A.1.12.2









The lactate/pyruvate:H+ symporter. Residues in the substrate translocation pathway have been reported (Soares-Silva et al., 2011).

Eukaryota
Fungi
Jen1 (YKL217w) of Saccharomyces cerevisiae
2.A.1.13:  The Monocarboxylate Porter (MCP) Family (Halestrap, 2011)
2.A.1.13.1









The proton-linked monocarboxylate (lactate, pyruvate, mevalonate, branched chain oxo acids, β-hydroxybutyrate, γ-hydroxybutyrate, butyrate, acetoacetate acetate and formate) uptake/efflux porter (Moschen et al. 2012). Activity is stimulated by direct interaction with carbonic anhydrase isoform II (Becker et al., 2005). This transporter interacts physically with the chaperone protein Basigin (CD147; TC #8.A.23.1.1) which is required both for targetting to the plasma membrane and for activity. Mct-2 uses a different chaperone protein, GP70. Mct-1 also transports the methionine hydroxy analogue 2-hydroxy (4-methylthio) butanate (Martin-Venegas et al., 2007). Activity is stimulated by binding of carbonic anhydrase II (Becker and Deitmer, 2008). MCT1, 3 and 4 require the ancillary protein, basigin (P35613; 8.A.23.1.1) for plasma membrane localization (Ovens et al., 2010).  Partially localizes to the peroxysomal membrane (Visser et al. 2007). MCT1 is regulated by CD147 proteins, and this association is important for lactate export and cell proliferation in certain cancer cells (Walters et al. 2013).  Upregulated in some cancers and maintains the metabolic phenotype of these cancer cells by mediating lactate efflux together with a proton, promoting pH homeostasis (PMID 24921258).  Also transports the chemotheraputic agent, 3-bromopyruvate (Cooper et al. 1989).

Eukaryota
Metazoa
MCT1 (SLC16A1) of Homo sapiens
2.A.1.13.2









The low affinity aromatic amino acid (Tyr, Trp, Phe) transporter, TAT1, MCT10, Slc16a10.  Also transports N-methyl amino acids.  Essential for aromatic amino acid homeostasis in various tissues of mice (Mariotta et al. 2012).

Eukaryota
Metazoa
Tat1 of Rattus norvegicus
2.A.1.13.3









The thyroid hormone transporter, MCT8 (transports L- and D-isomers of thyroxine (T4), 3,3',5-triiodothyronine (T3), 3,3'5'-triiodothyronine (rT3) and 3,3'-diiodothyronine [Km values = 2-5 μM; Leu, Phe, Trp and Tyr were not transported]) (Friesema et al., 2003). Loss of function mutations in MCT8 leads to Allan-Herndon-Dudley syndrome, severe X-linked psychomotor retardation and elevated serum T3 levels (Jansen et al., 2008). Essential molecular determinants for thyroid hormone transport and their structural implications are presented by Kinne et al. (2010). Induced by retinoic acid (Kogai et al., 2010). Mediates energy-independent bidirectional transport. MCT8 is specific for L-iodothyronines and requires at least one iodine atom per aromatic ring. Thyronamines, decarboxylated metabolites of iodothyronines, triiodothyroacetic acid and tetraiodothyroacetic acid, TH derivatives lacking both chiral center and amino group, are not substrates (Kinne et al., 2010). A deficiency causes altered thyroid morphology and a persistent high triiodothyronine/thyroxine ratio after thyroidectomy (Wirth et al., 2011). Primary and secondary thyroid hormone transporters have been reviewed (Kinne et al., 2011).

Eukaryota
Metazoa
MCT8 of Mus musculus (O70324)
2.A.1.13.4









The high affinity (17 μM) facilitated diffusion, riboflavin-regulated riboflavin uptake system, Mch5 (Reihl and Stolz, 2005)

Eukaryota
Fungi
Mch5 of Saccharomyces cerevisiae (NP_014951)
2.A.1.13.5









Monocarboxylate transporter-2 (MCT2). Transports γ-hydroxybutyrate (Wang and Morris, 2007). MCT2 requires the ancillary protein, embigin (Q6PCB8; 8.A.23.1.2) for plasma membrane localization (Ovens et al., 2010).  Partially localizes to the peroxysomal membrane (Visser et al. 2007).

Eukaryota
Metazoa
MCT2 (SLC16A7) of Homo sapiens
2.A.1.13.6









Plasma membrane proton-linked monocarboxylate transporter, MCT4 (SLC16A3). Catalyzes the rapid plasma membrane transport of many monocarboxylates such as lactate, pyruvate, branched-chain oxo acids derived from leucine, valine and isoleucine, and the ketone bodies acetoacetate, beta-hydroxybutyrate and acetate.  Catalyzes lactate efflux from glycolyzing cells (Halestrap 2013).  Residues involved in high affinity inhibitors have been identified (Nancolas et al. 2015).

Eukaryota
Metazoa
MCT4 (SLC16A3) of Homo sapiens
2.A.1.13.7









Monocarboxylate transporter-5 (MCT5 or SLC16A4; sometimes referred to as MCT4). Lactate transport via the MCT5 is non enzymatically stimulated by carbonic anhydrase II (Becker et al., 2010). MCTs require an ancillary 1TMS glycoprotein, either Embigin (Q6PCB8; TC# 8.A.23.1.2) or basigin (P35613; TC# 8.A.23.1.1) for plasma membrane localization (Ovens et al., 2010).  Upregulated in some cancers and maintains the metabolic phenotype of these cancer cells by mediating lactate efflux together with a proton, promoting pH homeostasis (Baltazar et al. 2014).  Also transports the chemotheraputic agent, 3-bromopyruvate (Baltazar et al. 2014).

Eukaryota
Metazoa
SLC16A4 of Homo sapiens
2.A.1.13.8









Monocarboxylate transporter, MCTI0. Transports thyroid horomones (Visser et al., 2010). Primary and secondary thyroid hormone transporters have been reviewed (Kinne et al., 2011).

Eukaryota
Metazoa
SLC16A10 of Homo sapiens
2.A.1.13.9









Short chain monocarboxylate (lactate) transporter 3, MCT3. MCT1, 3 and 4 require the ancillary protein, basigin (P35613; 8.A.23.1.1) for plasma membrane localization (Ovens et al., 2010).

Eukaryota
Metazoa
SLC16A8 of Homo sapiens
2.A.1.13.10









MCT8 (SLC16a2) homodimeric monocarboxylate thyroid hormone transporter 8 (Visser et al. 2009; Arjona et al., 2011).  The X-linked mental retardation Allan-Herndon-Dudley syndrome (AHDS) protein (Schweizer and Köhrle 2012).  AHDS is accompanied by several severe physiological symptoms (Boccone et al. 2010).  Arg residues important for function have been identified (Groeneweg et al. 2013).  Thyroid hormone transporters in the brain and across the blood brain barrier have been reviewed (Wirth et al. 2014) and (Bernal et al. 2015).

Eukaryota
Metazoa
SLC16A2 of Homo sapiens
2.A.1.13.11









solute carrier family 16, member 5 (monocarboxylic acid transporter 6)
Eukaryota
Metazoa
SLC16A5 of Homo sapiens
2.A.1.13.12









solute carrier family 16, member 14 (monocarboxylic acid transporter 14)
Eukaryota
Metazoa
SLC16A14 of Homo sapiens
2.A.1.13.13









solute carrier family 16, member 11 (monocarboxylic acid transporter 11)
Eukaryota
Metazoa
SLC16A11 of Homo sapiens
2.A.1.13.14









solute carrier family 16, member 12 (monocarboxylic acid transporter 12)
Eukaryota
Metazoa
SLC16A12 of Homo sapiens
2.A.1.13.15









Monocarboxylate transporter 7 (MCT 7) (Monocarboxylate transporter 6) (MCT 6) (Solute carrier family 16 member 6)
Eukaryota
Metazoa
SLC16A6 of Homo sapiens
2.A.1.13.16









Monocarboxylate transporter 9 (MCT 9) (Solute carrier family 16 member 9)
Eukaryota
Metazoa
SLC16A9 of Homo sapiens
2.A.1.13.17









Monocarboxylate transporter 13 (MCT 13) (Solute carrier family 16 member 13)
Eukaryota
Metazoa
SLC16A13 of Homo sapiens
2.A.1.13.18









Probable transporter MCH2
Eukaryota
Fungi
MCH2 of Saccharomyces cerevisiae S288c
2.A.1.13.19









Probable transporter MCH4
Eukaryota
Fungi
MCH4 of Saccharomyces cerevisiae
2.A.1.13.20









Putative permease of 468 aas

Eukaryota
Bangiophyceae
Putative permease of Galdieria sulphuraria
2.A.1.13.21









MFS porter of 392 aas

Bacteria
Proteobacteria
MSF porter of Pseudomonas stutzeri
2.A.1.13.22









SLC16 Family protein of 771 aas and 12 TMSs, GEM-1.  GEM-1 acts in parallel to the GON-2 channel (TC# 1.A.4.5.10) to promote cation uptake within the developing gonad (Kemp et al. 2009).

Eukaryota
Metazoa
Gem1 of Caenorhabditis elegans
2.A.1.14:  The Anion:Cation Symporter (ACS) Family
2.A.1.14.1









Glucarate porter
Bacteria
Firmicutes
GudT of Bacillus subtilis
2.A.1.14.2









Hexuronate (glucuronate; galacturonate)
porter, ExuT (Nemoz et al. 1976).

Bacteria
Proteobacteria
ExuT of E. coli (P0AA78)
2.A.1.14.3









Putative tartrate porter
Bacteria
Proteobacteria
TtuB of Agrobacterium vitis
2.A.1.14.4









Dipeptide (e.g., Gly-Leu), allantoate, ureidosuccinate, allantoin porter (Cai et al., 2007).
Eukaryota
Fungi
Dal5 of Saccharomyces cerevisiae
2.A.1.14.5









Phthalate porter
Bacteria
Proteobacteria
Pht1 of Pseudomonas putida
2.A.1.14.6









Na:Pi symporter, NPT1 or SLC17A1. (Renal chloride-dependent polyspecific anion exporter; transports organic acids such as p-aminohippurate, ureate, and acetylsalicylate (asprin)). Catalyzes ureate excretion. A mutant form shows increased risk of gout in humans.

Eukaryota
Metazoa
Npt1 of Mus musculus
2.A.1.14.7









Galactonate transporter
Bacteria
Proteobacteria
DgoT (YidT) of E. coli (P0AA76)
2.A.1.14.8









Phthalate porter
Bacteria
Proteobacteria
OphD of Burkholderia cepacia
2.A.1.14.9









Putative p-hydroxyphenylacetate porter
Bacteria
Proteobacteria
HpaX of Salmonella dublin
2.A.1.14.10









Lysosomal sialate transporter (Salla disease and infantile sialate storage disease protein (Morin et al., 2004)). Also transports glucuronic acid and aspartate. Structure-function studies have identify crucial residues and substrate-induced conformational changes (Courville et al., 2010). Also called SLC17A5. The substrate binding pocket has been identified based on modeling studies (Pietrancosta et al., 2012).  NAAG (N-acetylaspartylglutamate) an abundant neuropeptide in the vertebrate nervous system that is released from synaptic terminals in a calcium-dependent manner and acts as an agonist at the type II metabotropic glutamate receptor mGluR3, is transported into synaptic vesicles before it is secreted. Lodder-Gadaczek et al. 2013 demonstrate that vesicular uptake of NAAG and the related peptide NAAG2 (N-acetylaspartylglutamylglutamate) is mediated by sialin (SLC17A5). Sialin is probably the only vesicular transporter for NAAG and NAAG2, because transport of both peptides was not detectable in vesicles isolated from sialin-deficient mice.  Sialin also transports nitrate in the plasma membrane of salivary glands (Qin et al. 2012).

Eukaryota
Metazoa
SLC17A5 of Homo sapiens
2.A.1.14.11









Plasma membrane, high affinity nicotinate permease, Tna1
Eukaryota
Fungi
Tna1 of Saccharomyces cerevisiae
2.A.1.14.12









Plasma membrane, high affinity biotin:H+ symporter, Vht1
Eukaryota
Fungi
Vht1 of Saccharomyces cerevisiae
2.A.1.14.13









Broad specificity brain synaptic vesicle anion:Na+ symporter (transports glutamate, phosphate, chloride, etc.)(BNPI, EAT-4, VGLUT1) Chloride and ketone bodies regulate VGLUT activities (Omote et al., 2011). 

Eukaryota
Metazoa
BNPI of Rattus norvegicus
2.A.1.14.14









Probable D-galactarate (glucarate?):H+ symporter, GarP or YhaU.  May also function as a glucarate:glycerate antiporter (Moraes and Reithmeier 2012).

Bacteria
Proteobacteria
GarP (YhaU) of E. coli
2.A.1.14.15









Apical membrane renal proximal tubule. Voltage-driven but Na+-independent organic anion transporter, OATv1 (transports p-aminohippurate; probably transports organic anions but not cations and not inorganic phosphate. It may catalyze excretion of various drugs, xenobiotics, and their metabolites) (Jutabha et al., 2003)
Eukaryota
Metazoa
OATv1 of Sus scrofa (Q7YQJ7)
2.A.1.14.16









The broad specificity brain synaptic vesicle anion transporter (transports glutamate in a Δψ-dependent fashion requiring Cl- but phosphate by a Na+-dependent mechanism via a different pathway/mechanism (Juge et al., 2006). VGLUT1-3 concentrate glutamate into synaptic vesicles before its exocytotic release.

Eukaryota
Metazoa
VGLUT2 of Rattus norvegicus (Q9JI12)
2.A.1.14.17









Pantothenate:H+ symporter, Liz1 (mutants cause abnormal mitosis due to a defect in ribonucleotide reductase) (Stolz et al., 2004)
Eukaryota
Fungi
Liz1 of Schizosaccharomyces pombe (O43000)
2.A.1.14.18









Pantothenate:H+ symporter, Fen2
Eukaryota
Fungi
Fen2 of Saccharomyces cerevisiae (P25621)
2.A.1.14.19









Plasma membrane, high affinity vitamin H transporter 1 (H+:biotin symporter), Vht1 (Stolz, 2003)
Eukaryota
Fungi
Vht1 of Schizosaccharomyces pombe (O13880)
2.A.1.14.20









Endoplasmic reticular cysteine transporter, Yct1 (Kaur and Bachhawat, 2007)

Eukaryota
Fungi
Yct1 of Saccharomyces cerevisiae (Q12235)
2.A.1.14.21









The vesicular purine nucleotide (ADP, ATP, GTP) transporter. (Found in synaptic vesicles and chromafin granules, SLC17A9 (Sawada et al., 2008)).
Eukaryota
Metazoa
SLC17A9 of Homo sapiens
2.A.1.14.22









The chloroplast thylakoid Na+:phosphate symporter, ANTR1 (512aas) (Pavón et al., 2008). Residues essential for function have been identified (Ruiz-Pavón et al., 2010). Functionally important amino acids have been identified (Ruiz-Pavón et al., 2010).

Eukaryota
Viridiplantae
ANTR1 of Arabidopsis thaliana (O82390)
2.A.1.14.23









Vesicular glutamate transporter #3 (VGLUT3) [Its absence in mice causes sensorineural deafness and seizures]. 70% identical to VGLUT2 (TC# 2.A.1.14.16) (Gras et al., 2002). VGLUT1-3 concentrate glutamate into synaptic vesicles before its exocytotic release and contribute to the regulation of serotonergic transmission and anxiety (Amilhon et al., 2010).

Eukaryota
Metazoa
VGLUT3 of Mus musculus (Q8BFU8)
2.A.1.14.24









Intestinal mucosal sodium/phosphate symporter, SLC17A4. Maintains phosphate homeostasis; mediates intestinal absorption, bone deposition and resorption and renal excretion.

Eukaryota
Metazoa
SLC17A4 of Homo sapiens
2.A.1.14.25









The putative D-mannuronate porter, AlgT (Rodionov et al., 2010).

Bacteria
Proteobacteria
AlgT of Shewanella frigidimarina (Q07YH1)
2.A.1.14.26









The plasma membrane Lethal (2)01810 glutamate uptake porter (Km=0.07μM) (Inhibited by aspartate) (Shim et al., 2011)

Eukaryota
Metazoa
L(2)01810 of Drosophila melanogaster (F2YPN7)
2.A.1.14.27









solute carrier family 17 (sodium phosphate), member 1
Eukaryota
Metazoa
SLC17A1 of Homo sapiens
2.A.1.14.28









solute carrier family 17 (sodium phosphate), member 3
Eukaryota
Metazoa
SLC17A3 of Homo sapiens
2.A.1.14.29









Sodium-dependent phosphate transport protein 3 (Na(+)/PI cotransporter 3) (Sodium/phosphate cotransporter 3) (Solute carrier family 17 member 2)
Eukaryota
Metazoa
SLC17A2 of Homo sapiens
2.A.1.14.30









Vesicular glutamate transporter 1, VGluT1. Brain-specific Na+-dependent inorganic phosphate cotransporter; Solute carrier family 17 member 7). Several proteins must be retrieved to the synatic vesicle before it can export neurotransmitters again, and cargo retrieval is a collective cargo-driven process, dependent on VGluT1 (Pan et al. 2015).

Eukaryota
Metazoa
SLC17A7 of Homo sapiens
2.A.1.14.31









Vesicular glutamate transporter 2 (VGluT2) (Differentiation-associated BNPI) (Differentiation-associated Na(+)-dependent inorganic phosphate cotransporter) (Solute carrier family 17 member 6)
Eukaryota
Metazoa
SLC17A6 of Homo sapiens
2.A.1.14.32









Vesicular glutamate transporter 3 (VGluT3) (Solute carrier family 17 member 8)
Eukaryota
Metazoa
SLC17A8 of Homo sapiens
2.A.1.14.33









Putative L-galactonate transporter, YjjL

Bacteria
Proteobacteria
YjjL of Escherichia coli
2.A.1.14.34









Putative inorganic phosphate cotransporter
Eukaryota
Metazoa
Picot of Drosophila melanogaster
2.A.1.14.35









Inner membrane transport protein RhmT
Bacteria
Proteobacteria
RhmT of Escherichia coli
2.A.1.14.36









Thiamine pathway transporter THI73
Eukaryota
Fungi
THI73 of Saccharomyces cerevisiae
2.A.1.14.37









Probable transporter SEO1
Eukaryota
Fungi
SEO1 of Saccharomyces cerevisiae
2.A.1.14.38









Uncharacterized transporter YIL166C
Eukaryota
Fungi
YIL166C of Saccharomyces cerevisiae
2.A.1.14.39









Uncharacterized transporter YybO
Bacteria
Firmicutes
YybO of Bacillus subtilis
2.A.1.14.40









Glucarate transporter, GudP.  Encoded in an operon with GudD, a glucarate dehydratase (Moraes and Reithmeier 2012).

Bacteria
Proteobacteria
GudP of E. coli
2.A.1.14.41









The Aldohexuronate (glucuronate, galacturonate) uptake porter (Valmeekam et al. 2001).

Bacteria
Proteobacteria
ExuT of Erwinia chrysanthemi  This sequence is incomplete.
2.A.1.14.42









Vesicular glutamate transporter, EAT-4/VGLUT of 576 aas (Serrano-Saiz et al. 2013).  EAT-4 is responsible for loading glutamate into synaptic vesicles, and thus in defining the glutamatergic phenotype of a neuron (Serrano-Saiz et al. 2013). 

Eukaryota
Metazoa
EAT-4 of Caenorhabditis elegans
2.A.1.15:  The Aromatic Acid:H+ Symporter (AAHS) Family
2.A.1.15.1









4-Hydroxybenzoate/protocatachuate porter
Bacteria
Proteobacteria
PcaK of Pseudomonas putida
2.A.1.15.2









MhpT. A specific 3-(3-hydroxyphenyl)propionate (3HPP) transporter; vital for E. coli K-12 W3110 to grow on this substrate.  Transports 3HPP but not benzoate, 3-hydroxybenzoate or gentisate (Xu et al. 2013).  May also export arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
MhpT of E. coli
2.A.1.15.3









2,4-Dichlorophenoxyacetate porter
Bacteria
Proteobacteria
TfdK of Ralstonia eutropha
2.A.1.15.4









cis,cis-muconate porter, MucK (Williams and Shaw 1997).

Bacteria
Proteobacteria
MucK of Acinetobacter sp. ADP1
2.A.1.15.5









Benzoate porter, BenK
Bacteria
Proteobacteria
BenK of Acinetobacter sp. ADPP1
2.A.1.15.6









Vanillate porter, VanK

Bacteria
Proteobacteria
VanK of Acinetobacter sp. ADP1
2.A.1.15.7









Aromatic compound (benzoate) uptake transporter of 450 aas (Clark et al. 2002).

Bacteria
Proteobacteria
BenK of Acinetobacter baylyi
2.A.1.15.8









Probable 1-hydroxy-2-naphthoate transporter, orf1 (Iwabuchi and Harayama, 1997).
Bacteria
Actinobacteria
Orf1 of Nocardioides sp. (O24723)
2.A.1.15.9









Probable 4-methylmuconolactone transporter, MmlH (Erb et al., 1998)
Bacteria
Proteobacteria
MmlH of Ralstonia eutropha (O51798)
2.A.1.15.10









The gentisate (2,5-dihydroxybenzoate) uptake porter, GenK (does not take up either benzoate or 3-hydoxybenzoate).

Bacteria
Actinobacteria
GenK of Corynebacterium glutamicum (Q8NLB7)
2.A.1.15.11









The Vanillate porter, VanK 

Bacteria
Actinobacteria
VanK of Corynebacterium glutamicum (Q6M372)
2.A.1.15.12









Inner membrane transport protein YdiM

Bacteria
Proteobacteria
YdiM of Escherichia coli
2.A.1.15.13









Inner membrane transport protein YdiN (Similar to 2.A.1.15.12)

Bacteria
Proteobacteria
YdiN of Escherichia coli
2.A.1.15.14









Probable uptake transporter for 2,4-dichlorophenoxyacetic acid (2,4-D), CadK (Kitagawa et al. 2002).

Bacteria
Proteobacteria
CadK of Bradyrhizobium sp. HW13
2.A.1.15.15









MFS Homologue

Bacteria
Actinobacteria
MFS homologue of Streptomyces coelicolor (Q9RL01)
2.A.1.15.16









MFS uptake permease.  The gene is adjacent to a putative SAM-dependent methyl transferase, one homologue of which is a puromycin methyl transferase.  Perhaps the transport substrate is a drug that is modified by methylation for detoxification purposes. 

Bacteria
Proteobacteria
MFS uptake permease of Myxococcus xanthus
2.A.1.15.17









Fused protein with N-terminal transmembrane region of 7 putative TMSs and a C-terminal hydrophilic domain homologous to SAM-dependent spermidine synthase.  The N-terminus of this protein shows extensive sequence similarity with 2.A.1.15.16 but shows weak similarity with other MFS permeases.

Bacteria
Proteobacteria
Fused protein of Thiocapsa marina
2.A.1.15.18









Unncharacterized permease of 436 aas and 12 TMSs.

Bacteria
Spirochaetes
UP of Treponema brennaborense
2.A.1.16:  The Siderophore-Iron Transporter (SIT) Family
2.A.1.16.1









Siderophore-iron (ferrioxamine):H+ sym-
porter, Sit1 (Arn3) (in vesicles)
Eukaryota
Fungi
Sit1 (YEL065w) of Saccharomyces cerevisiae
2.A.1.16.2









The ferric enterobactin:H+ symporter, Enb1
Eukaryota
Fungi
Enb1 (YOL158c) of Saccharomyces cerevisiae
2.A.1.16.3









The ferric triacetylfusarinine C:H+ symporter, Taf1
Eukaryota
Fungi
Taf1 (YHL047c) of Saccharomyces cerevisiae
2.A.1.16.4









The ferrichrome:H+ symporter, Arn1p (Moore et al., 2003)
Eukaryota
Fungi
Arn1 of Saccharomyces cerevisiae (NP_011823)
2.A.1.16.5









Siderophore iron transporter 2
Eukaryota
Fungi
str2 of Schizosaccharomyces pombe
2.A.1.16.6









Siderophore iron transporter 1,
Str1

Eukaryota
Fungi
Str1 of Schizosaccharomyces pombe
2.A.1.16.7









Ferri-siderophore transporter, MirB. Transports hydroxamate siderophores such as triacetylfusarinine C (TAFC) (Raymond-Bouchard et al. 2012).

Eukaryota
Fungi
MirB of Emericella nidulans
2.A.1.17:  The Cyanate Porter (CP) Family
2.A.1.17.1









Cyanate transport system, CynT.  Encoded with cyanate aminohydrolase, CynS, and carbonic anhydrase, CynX (Anderson et al. 1990; Moraes and Reithmeier 2012).

Bacteria
Proteobacteria
CynX of E. coli
2.A.1.17.2









Glucose transporter, OEOE_0819. Does not transport fructose (Kim et al., 2011)

Bacteria
Firmicutes
OEOE_0819 of Oenococcus onei (Q04FN1)
2.A.1.17.3









Inner membrane transport protein YeaN

Bacteria
Proteobacteria
YeaN of Escherichia coli
2.A.1.18:  The Polyol Porter (PP) Family
2.A.1.18.1









D-Arabinitol:H+ symporter
Bacteria
Proteobacteria
DalT of Klebsiella pneumoniae
2.A.1.18.2









Ribitol:H+ symporter
Bacteria
Proteobacteria
RbtT of Klebsiella pneumoniae
2.A.1.18.3









Alpha-ketoglutarate permease
Bacteria
Firmicutes
CsbX of Bacillus subtilis
2.A.1.19:  The Organic Cation Transporter (OCT) Family (The SLC22A family including OCT1-3, OCTN1-3 and OAT1-5 of H. sapiens)

This family has been described by Koepsell 2013.  It contains 13 functionally characterized human plasma membrane proteins.The family includes organic cation transporters (OCTs), organic zwitterion/cation transporters (OCTNs), and organic anion transporters (OATs). The transporters operate as (1) uniporters which mediate facilitated diffusion (OCTs and some OCTNs), (2) anion exchangers (OATs), and (3) some Na+/zwitterion cotransporters (OCTNs). They participate in small intestinal absorption and hepatic and renal excretion of drugs, xenobiotics and endogenous compounds and perform homeostatic functions in the brain and heart. Important endogeneous substrates include monoamine neurotransmitters, l-carnitine, alpha-ketoglutarate, cAMP, cGMP, prostaglandins and urate. Mutations in the SLC22 genes cause specific diseases like primary systemic carnitine deficiency and idiopathic renal hypouricemia and are correlated with diseases such as Crohn's disease and gout. Drug-drug interactions at individual transporters may change pharmacokinetics and toxicities of drugs (Koepsell 2013).

2.A.1.19.1









The basolateral multivalent, potential-sensitive, organic cation (tetramethyl-ammonium; N'-methylnicotinamide; cationic drugs, xenobiotics, vitamins, neuro-transmitters, etc.) transporter (uni-porter)-1, Oct1
Eukaryota
Metazoa
Oct1 of Rattus norvegicus (Q63089)
2.A.1.19.2









The ergothionine/organic cation porter, OctN1 (SLC22A4). Associated with rheumatoid arthritis (Barton et al., 2005).  Acetylcholine is a physiological substrate, and its transport could be involved in nonneuronal cholinergic functions (Pochini et al. 2013).  OCTN1 and OCTN2 are associated with several pathologies, such as inflammatory bowel disease, primary carnitine deficiency, diabetes, neurological disorders, and cancer.

Eukaryota
Metazoa
OctN1 of Homo sapiens (O14546)
2.A.1.19.3









The polyspecific organic cation (L- and D-carnitine, butyryl-L-carnitine, acetyl carnitine, γ-butyro-betaine, glycinebetaine, β-lactam antibiotics with a quaternary nitrogen such as cephaloridine, and others):Na+ symporter, OctN2 (SLC22A5). Associated with Crohn''s disease (Barton et al., 2005) as well as primary carnitine deficiency.  The protein is glycosylated on extracytoplasmic asparagines, and these residues are in a region important for function and turnover (Filippo et al. 2011).  OCTN2 maintains the carnitine homeostasis, resulting from intestinal absorption, distribution to tissues, and renal excretion/reabsorption (Pochini et al. 2013).  OCTN1 and OCTN2 are associated with several pathologies, such as inflammatory bowel disease, primary carnitine deficiency, diabetes, neurological disorders, and cancer.  OctN2 is activated in a process dependent on Caveolin1 (Q03135)which interacts directly with OctN2 and by protein kinase C which does not phosphorylate OctN2 directly (Czeredys et al. 2013).

Eukaryota
Metazoa
SLC22A5 of Homo sapiens
2.A.1.19.4









The polyspecific organic anion, cation and neutral molecule transporter, Oat1 (Slc22a6) (transports neutral compounds such as cardiac glycosides [i.e., ouabain] and steroids [i.e., aldosterone; cortisol; dexamethasone]; cationic compounds such as N-propylajmalinium, and anionic compounds such as p-aminohippurate, dicarboxylates, cyclic nucleotides, prostaglandins, urate, β-lactam antibiotics, nonsteroidal anti-inflammatory drugs, diuretics, bile salts and steroid conjugates [i.e., estrone-3-sulfate and estradiol-17-glucuronide]) transporter (H+ symporter or uniporter) Probably catalyzes organic anion (uptake):dicarboxylate (efflux) antiport in the basolateral membrane of kidney proximal tubules) (Eraly et al., 2003a,b). A 3-dimensional model of OAT1 has led to the identification of residues involved in differential transport of substrates such as p-aminohippurate and cidofovir (Perry et al., 2006). Oat1 transports many antiviral agents (Truong et al., 2008).  The human orthologue (Q4U2R8; 563aas) has been shown to be a multispecific organic anion transporter on the basolateral membrane of the proximal tubule in human kidney (Hosoyamada et al. 1999). A substrate binding hinge domain is required for transport-related structural changes (Egenberger et al., 2012). Transports environmental toxins and clinically important drugs including anti-HIV therapeutics, anti-tumor drugs, antibiotics, anti-hypertensives, and anti-inflammatories (Duan et al., 2011). hOAT1 has two GXXXG motifs in TMSs 2 and 5 which play critical roles in stability (Duan et al., 2011).  Both OAT1 and OAT3 of humans are inhibited by caffeic acid (Ki ~ 17 μM) (Uwai et al. 2011).

Eukaryota
Metazoa
Oat1 of Rattus norvegicus (O35956)
2.A.1.19.5









The putative apical polyspecific organic cation transporter (cation:H+ or cation:cation antiporter), Oct2 (substrates include monoamine neurotransmitters such as dopamine, noradrenaline, adrenaline and 5-hydroxytryptamine) (Oct2 exhibits some properties of an ion channel with an inner diameter of ~4 Å. Selectivity: Cs+ > Rb+ > K+ > Na+ %u2248 Li+ (Schmitt and Koepsell, 2005)) Chloride dependent, but a single mutation (R466K) abolishes this dependency (Rizwan et al., 2007). Also transports ochratoxin (Rizwan et al., 2007) and cisplatin and oxaliplatin (Yonezama et al., 2006).

Eukaryota
Metazoa
Oct2 of Sus scrofa (O02713)
2.A.1.19.6









The polyspecific potential-sensitive organic cation uptake transporter, Oct3 (transport substrates include the neurotoxin 1-methyl-4-phenylpyridinium and monoamine neurotransmitters such as dopamine). Mediates paraquat (herbicide) neurotoxicity (Rappold et al., 2011).

Eukaryota
Metazoa
Oct3 of Rattus norvegicus (O88446)
2.A.1.19.7









The polyspecific organic anion (and cation) (anions: p-aminohippurate, ochratoxin A, estrone sulfate, anionic drugs, anionic neurotransmitter metabolites; cation: cimetidine) transporter, Oat3 (slc22a8) (catalyzes organic anion (uptake): dicarboxylate (efflux) antiport in the basolateral membrane of the renal proximal tubule) (Eraly et al., 2003a,b); transports many antiviral agents (Truong et al., 2008).
Eukaryota
Metazoa
Oat3 of Rattus norvegicus (Q9R1U7)
2.A.1.19.8









The human organic cation transporter, SLC22A17.  The rat orthologue may be inactive (Bennett et al. 2011).

It is also the cell surface receptor for Lipocalin-2 (LCN2; 24p3) that plays a key role in iron homeostasis and transport. Able to bind iron-bound LCN2, followed by internalization and release of iron, thereby increasing intracellular iron concentration and leading to inhibition of apoptosis. Also binds iron-free LCN2, followed by internalization and its association with an intracellular siderophore, leading to iron chelation and iron transfer to the extracellular medium, thereby reducing intracellular iron concentration and resulting in apoptosis.

Eukaryota
Metazoa
SLC22A17 of Homo sapiens
2.A.1.19.9









The osteosclerosis protein, Roct (organic anion transporter 3, Oat3) (Slc22a8) (catalyzes organic anion (uptake):di-carboxylate (efflux) antiport in the basolateral membrane of the renal proximal tubule) (Eraly et al., 2003a,b); transports glutathione and many antiviral agents (Truong et al., 2008).  It is a multispecific drug transporter, critical for the renal handling of common drugs (e.g, antibiotics, antivirals, diuretics) and toxins.  Probably handles hydroxylated and glucouronidated metabolites, consistent with the "remote sensing and signaling hypothesis" (Wu et al. 2013).  It may also handle dietary flavonoids and antioxidants.

Eukaryota
Metazoa
Roct (Oat3) of Mus musculus (O88909)
2.A.1.19.10









The apical proximal tubular kidney/placenta organic anion transporter 4, Oat4 (Slc22a11) (transports estrone sulfate (Km = 1 µM), dehydroepiandrosterone sulfate (Km = 60µM), many anionic drugs, diuretics, bile salts, and ochratoxin A) (catalyzes Na+-independent efflux).
Eukaryota
Metazoa
SLC22A11 of Homo sapiens
2.A.1.19.11









The apical proximal tubular renal urate:anion exchanger, URAT1 (Slc22a12) (catalyzes Na+-independent anion efflux (secretion)) (Eraly et al., 2003a,b; Anzai and Endou, 2011) (regulated by PDZK1 protein; Anzai et al., 2004). Also transports orotate, a precursor of pyrimidine biosynthesis (Miura et al., 2011). Mutations in URAT1 cause hereditary renal hypouricemia.

Eukaryota
Metazoa
SLC22A12 of Homo sapiens
2.A.1.19.12









The high affinity L-carnitine transporter, CT2 (present in the luminal membranes of epididymal epithelia and Sertoli cells of the testis) (Enomoto et al., 2002b)

Eukaryota
Metazoa
SLC22A16 of Homo sapiens
2.A.1.19.13









The organic cation transporter, Oct1 (transports L-carnitine; expressed in vascular tissues of various organs and at sites of lateral root formation) (Lelandais-Briere et al, 2007)
Eukaryota
Viridiplantae
Oct1 of Arabidopsis thaliana (Q9CAT6)
2.A.1.19.14









Brush boarder glycosylated urate (Km= 1.2 mM) tranporter, RST. orthologous to the human URAT1. Inhibited by 50 μM benzbromarone, 1 mM probenecid and 10 mM lactate which may also be transported and trans-stimulate urate uptake. May be orthologous to 2.A.1.19.11. (Hosoyamada et al., 2004).  Involved in urate absorption, but probably not the primary route (Eraly et al. 2008).

Eukaryota
Metazoa
URAT1 of Mus musculus
(Q8CFZ5)
2.A.1.19.15









The liver multispecific organic anion transporter, NLT or OAT2. Transports salicylate, KM=90µM, acetylsalicylate, prostaglandin E2, dicarboxylate, p-aminohippurate, etc. (Sekine et al., 1998)
Eukaryota
Metazoa
NLT of Rattus norvegicus (Q63314)
2.A.1.19.16









The organic anion transporter, Oat6 (binding and transport rates for 40 anionic substrates were studied and compared with these for Oat1 (TC# 1.A.1.19.4) (Kaler et al., 2007); transports many antiviral agents (Truong et al., 2008).

Eukaryota
Metazoa
Oat6 of Mus musculus (Q80UJ1)
2.A.1.19.17









Kidney organic cation transporter-like 3 ORCTL-3 (OAT10; SLC22A13; Like-3) (Bahn et al., 2008) (transports nicotinate, p-aminohippurate and urate; KM=20-40 mμM) via exchange for lactate).  Activated by tumorigeneic mutations in this antitumor gene to promote apoptosis (AbuAli and Grimm 2014).

Eukaryota
Metazoa
SLC22A13 of Homo sapiens
2.A.1.19.18









Oranic anion transporter, Oat7 (exchanges sulfate conjugates (steroids) and other anions for butyrate) (Shin et al., 2007)
Eukaryota
Metazoa
SLC22A9 of Homo sapiens
2.A.1.19.19









The rat kidney basolateral potential-driven symport carrier, Oct2 (transports tetraethylammonium and many other organic cations) (Sweet and Pritchard 1999).
Eukaryota
Metazoa
Oct2 of Rattus norvegicus (Q9R0W2)
2.A.1.19.20









Prostaglandin (PGE2, PGE2α, and PGD(2)) -specific organic anion transporter. Exhibits Na+ -independent and saturable transport. Shows narrow substrate selectivity and high affinity (Shiraya et al., 2010).

Eukaryota
Metazoa
OAT-PG of Homo sapiens (Q8R0S9)
2.A.1.19.21









solute carrier family 22, member 24
Eukaryota
Metazoa
SLC22A24 of Homo sapiens
2.A.1.19.22









solute carrier family 22, member 14
Eukaryota
Metazoa
SLC22A14 of Homo sapiens
2.A.1.19.23









solute carrier family 22, member 31
Eukaryota
Metazoa
SLC22A31 of Homo sapiens
2.A.1.19.24









Solute carrier family 22 member 3 (Extraneuronal monoamine transporter) (EMT) (Organic cation transporter 3)
Eukaryota
Metazoa
SLC22A3 of Homo sapiens
2.A.1.19.25









Solute carrier family 22 member 7 (Novel liver transporter) (Organic anion transporter 2) (hOAT2)
Eukaryota
Metazoa
SLC22A7 of Homo sapiens
2.A.1.19.26









Solute carrier family 22 member 4; Ergothioneine transporter (ET) (Organic cation/carnitine transporter 1) (Bacher et al. 2009).

Eukaryota
Metazoa
SLC22A4 of Homo sapiens
2.A.1.19.27









Solute carrier family 22 member 10 (Organic anion transporter 5)
Eukaryota
Metazoa
SLC22A10 of Homo sapiens
2.A.1.19.28









Solute carrier family 22 member 23.  The rat orthologue may be inactive (Bennett et al. 2011).

Eukaryota
Metazoa
SLC22A23 of Homo sapiens
2.A.1.19.29









Solute carrier family 22 member 1 (Organic cation transporter 1) (hOCT1).  May be a primary polyamine uptake porter (Abdulhussein and Wallace 2013).

Eukaryota
Metazoa
SLC22A1 of Homo sapiens
2.A.1.19.30









Solute carrier family 22 member 2 (Organic cation transporter 2) (hOCT2).  Oct2 is a low affinity high efficiency choline transporter, enriched in synaptic vesicles of cholinergic neurons (Nakata et al. 2013).

Eukaryota
Metazoa
SLC22A2 or Oct2 of Homo sapiens
2.A.1.19.31









Solute carrier family 22 member 6 (Organic anion transporter 1) (hOAT1) (PAH transporter) (hPAHT) (Renal organic anion transporter 1) (hROAT1)
Eukaryota
Metazoa
SLC22A6 of Homo sapiens
2.A.1.19.32









Solute carrier family 22 member 15 (Fly-like putative transporter 1) (Flipt 1)
Eukaryota
Metazoa
SLC22A15 of Homo sapiens
2.A.1.19.33









Solute carrier family 22 member 25 (Organic anion transporter UST6)
Eukaryota
Metazoa
SLC22A25 of Homo sapiens
2.A.1.19.34









Multispecific drug transporter, solute carrier family 22 member 8 (Organic anion transporter 3) (hOAT3).  Both OAT1 and OAT3 of humans are inhibited by caffeic acid (Ki ~ 17 μM) (Uwai et al. 2011; Wu et al. 2013).  See also 2.A.1.19.9.

Eukaryota
Metazoa
SLC22A8 of Homo sapiens
2.A.1.19.35









Solute carrier family 22 member 20 (Organic anion transporter 6)
Eukaryota
Metazoa
SLC22A20 of Homo sapiens
2.A.1.19.36









Organic cation transporter protein. OrcT

Eukaryota
Metazoa
OrcT of Drosophila melanogaster
2.A.1.19.37









Organic cation transporter 1 (CeOCT1)
Eukaryota
Metazoa
Oct-1 of Caenorhabditis elegans
2.A.1.19.38









Uncharacterized MFS-type transporter PB1E7.08c
Eukaryota
Fungi
SPAPB1E7.08c of Schizosaccharomyces pombe
2.A.1.19.39









Organic cation/carnitine transporter 6 (AtOCT6)
Eukaryota
Viridiplantae
OCT6 of Arabidopsis thaliana
2.A.1.19.40









Organic anion transporter, Oat9.  A splice variant with 443 aas and 8 TMSs (Oa9S) was reported to transport L-carnitine (3 μM), cimetidine (16 μM) and salicylic acid (175 μM), but the full length protein of 551 aas and 12 TMSs (Oat9L) was reported to be inactive (Tsuchida et al. 2010).  

Eukaryota
Metazoa
Oat9 of Mus musculus
2.A.1.19.41









Organocation transporter, OCTN3.  Identified only in mouse; mediates carnitine transport (Pochini et al. 2013).  81% identical to 2.A.1.19.3.  Also called SLC22a21 and SLC22a9.

Eukaryota
Metazoa
OctN3 of Mus musculus
2.A.1.19.42









Slc22 homologue of 580 aas.

Eukaryota
Viridiplantae
Slc19 homologue of Ostreococcus tauri
2.A.1.19.43









Organocation transporter, Oct4 of 526 aas

Eukaryota
Viridiplantae
Oct4 of Arabidopsis thaliana (Mouse-ear cress)
2.A.1.19.44









Uncharacterized protein of 556 aas

Eukaryota
Viridiplantae
UP of Chlorella variabilis (Green alga)
2.A.1.19.45









MFS transporter of 569 aas

Eukaryota
Intramacronucleata
MFS transporter of Tetrahymena thermophila
2.A.1.19.46









MFS transporter of 593 aas

Eukaryota
Intramacronucleata
MFS porter of Oxytricha trifallax
2.A.1.19.47









MFS porter of 691 aas

Eukaryota
Viridiplantae
MFS porter of Volvox carteri (Green alga)
2.A.1.19.48









Fungal MFS homologue of 520 aas

Eukaryota
Fungi
UP of Aspergillus terreus
2.A.1.19.49









Putative glucose transporter 1 (Gluct1) of 569 aas and 12 TMSs.  Constitutively synthesized in many tissues.  Serves as the receptor of white spot syndrom virus (WSSV) (Huang et al. 2012). 

Eukaryota
Metazoa
Gluct1 of Litopenaeus vannamei (Whiteleg shrimp) (Penaeus vannamei)
2.A.1.19.50









Multispecific anion transporter, OatA1, of 526 aas and 12 TMSs.

Eukaryota
Metazoa
OatA1 of Caenorhabditis elegans
2.A.1.20:  The Sugar Efflux Transporter (SET) Family
2.A.1.20.1









Sugar efflux transporter A, SetA.  Exports lactose, glucose, aromatic glucosides and galactosides, cellobiose, maltose, α-methylglucoside, and isopropyl β-thiogalactosides (IPTG); amino-glycosides, streptomycin and kanamycin are weakly expelled (Liu et al. 1999).  REgulated by SgrR (a transcriptional reglator of sgrS) and SgrS (a small RNA) that represses trascription of setA.  These two regulatory genes are upstream of the setA gene.  Uses a pmf-dependent mechanism of energization.  Induced in response to glucose-phosphate stress which occurs when a sugar phosphate accumulates in the cytoplams (Sun and Vanderpool 2011).

Bacteria
Proteobacteria
SetA (YabM) of E. coli
2.A.1.20.2









Efflux system, SetB, for lactose and glucose, but not IPTG or galactose (Liu et al. 1999).

Bacteria
Proteobacteria
SetB (YeiO) of E. coli
2.A.1.20.3









Arabinose (but not xylose) exporter, SetC (Koita and Rao 2012).

Bacteria
Proteobacteria
SetC (YicK) of E. coli
2.A.1.20.4









Efflux system for arabinose and IPTG (>>lactose), SotA
Bacteria
Proteobacteria
SotA of Erwinia chrysanthemi
2.A.1.21:  The Drug:H+ Antiporter-3 (12 Spanner) (DHA3) Family
2.A.1.21.1









The macrolide (erythromycin; oleando-mycin; azithromycin) efflux, MefA
Bacteria
Firmicutes
MefA of Streptococcus pyogenes
2.A.1.21.2









The multidrug (erythromycin, tetracycline, puromycin, bleomycin) resistance protein,
Cmr
Bacteria
Actinobacteria
Cmr of Corynebacterium glutamicum
2.A.1.21.3









The tetracycline resistance determinant, TetV
Bacteria
Actinobacteria
TetV of Mycobacterium smegmatis
2.A.1.21.4









Multidrug resistance efflux pump, Tap
Bacteria
Actinobacteria
Tap of Mycobacterium fortuitum
2.A.1.21.5









The putative bacilysin exporter, BacE
Bacteria
Firmicutes
BacE of Bacillus subtilis (P39642)
2.A.1.21.6









The tetracycline resistance efflux pump, TetA(P) (Bannam et al., 2004) (21% identity (e-07) with 2.A.1.21.5 and 22% identity (2xe-7) with 2.A.1.2.10). It may be the link between DHA1 and DHA3.
Bacteria
Firmicutes
TetA (P) of Clostridium perfringens (Q46305)
2.A.1.21.7









The Staphyloferrin A (siderophore) exporter, NWMN-2081 (Beasley et al. 2009).
Bacteria
Firmicutes
NWMN-2081 of Staphylococcus aureus (A6QJ21)
2.A.1.21.8









The putative macrolide exporter, TIGR00900 (most similar to 2.A.1.21.1).

Bacteria
Firmicutes
TIGR00900 of Bacillus clausii (Q5WAS7)
2.A.1.21.9









MFS carrier of unknown function

Archaea
Euryarchaeota
MFS carrier of Thermoplasma acidophilum (Q9HLP1)
2.A.1.21.10









MFS porter

Archaea
Crenarchaeota
MFS porter of Sulfolobus islandicus (D2PCQ8)
2.A.1.21.11









MFS porter

Bacteria
Actinobacteria
MFS porter of Stackebrandtia nassauensis (D3Q871)
2.A.1.21.12









Probable multidrug-efflux transporter Rv1258c/MT1297
Bacteria
Actinobacteria
Rv1258c of Mycobacterium tuberculosis
2.A.1.21.13









Uncharacterized MFS-type transporter yjbB
Bacteria
Firmicutes
YjbB of Bacillus subtilis
2.A.1.21.14









Uncharacterized MFS-type transporter Mb0038c
Bacteria
Actinobacteria
Mb0038c of Mycobacterium bovis
2.A.1.21.15









MFS Homologue

Bacteria
Actinobacteria
MFS homologue of Streptomyces coelicolor (Q9X9Y0)
2.A.1.21.16









MFS Homologue

Bacteria
Actinobacteria
MFS homologue of Streptomyces coelicolor (Q9X8T4)
2.A.1.21.17









Uncharacterized MFS-type transporter YxaM

Bacteria
Firmicutes
YxaM of Bacillus subtilis
2.A.1.21.18









Uncharacterized protein

Bacteria
Actinobacteria
Uncharacterized protein of Streptomyces coelicolor
2.A.1.21.19









Uncharacterized Major Facilitator

Bacteria
Actinobacteria
UMF of Streptomyces coelicolor
2.A.1.21.20









Unidentified Major Facilitator

Bacteria
Proteobacteria
UMF of Pseudomonas syringae
2.A.1.21.21









Unidentified major facilitator

Bacteria
Actinobacteria
UMF of Saccharomonospora marina
2.A.1.21.22









Macrolide efflux pump, MefE (Mef; MefA) of 405 aas.  Induced by erythromycin and the antimicrobial peptide, LL-37 (Zähner et al. 2010).  May act in conjunction with Mel (Q93QE4), an ABC-type ATPase that is encoded in the same operon with the mefA gene (Ambrose et al. 2005).

Bacteria
Firmicutes
MefE of Streptococcus pneumoniae
2.A.1.22:  The Vesicular Neurotransmitter Transporter (VNT) Family (Related to the SP Family (TC #2.1.1))
2.A.1.22.1









Synaptic vesicle neurotransmitter (e.g., dopamine) transporter, SV2.  This protein localizes to neurotransmitter-containing vesicles and has a nucleotide binding site (Yao and Bajjalieh 2009).

Eukaryota
Metazoa
SV2 of Rattus norvegicus
2.A.1.22.2









Synaptic vesicle glycoprotein 2B of 556 aas

Eukaryota
Metazoa
Glycoprotein 2B of Tribolium castaneum
2.A.1.22.3









AgaP of 537 aas

Eukaryota
Metazoa
AgaP of Anopheles gambiae
2.A.1.22.4









Uncharacterized protein of 537 aas

Eukaryota
Metazoa
UP of Acyrthosiphon pisum
2.A.1.22.5









Uncharacterized protein of 561 aas

Eukaryota
Metazoa
UP of Trichoplax adhaerens (Trichoplax reptans)
2.A.1.23:  The Conjugated Bile Salt Transporter (BST) Family
2.A.1.23.1









Conjugated bile salt:H+ symporter, CbsT1
Bacteria
Firmicutes
CbsT1 of Lactobacillus johnsonii 100-100
2.A.1.23.2









Taurocholate:cholate antiporter, CbsT2
Bacteria
Firmicutes
CbsT2 of Lactobacillus johnsonii 100-100 (AAC34380)
2.A.1.24:  The Unknown Major Facilitator-1 (UMF1) Family
2.A.1.24.1









58.8 KDa protein, YCL038c
Eukaryota
Fungi
YCL038c of Saccharomyces cerevisiae
2.A.1.24.2









Putative vacuolar amino acid efflux porter, Atg22 (Autophagy-related protein-22)

Eukaryota
Fungi
Atg22 of Schizosaccharomyces pombe (Q09812)
2.A.1.24.3









MFS permease

Bacteria
Chloroflexi
MFS permease of Chloroflexus aurantiacus (A9WGR7)
2.A.1.24.4









MFS permease

Bacteria
Proteobacteria
MFS permease of Myxococcus xanthus (Q1CWQ3)
2.A.1.24.5









MFS permease

Bacteria
Actinobacteria
MFS permease of Micrococcus luteus (Micrococcus lysodeikticus)
2.A.1.24.6









MFS porter of 474 aas

Bacteria
Proteobacteria
MFS porter of Hyphomonas neptunium
2.A.1.25:  The Peptide-Acetyl-Coenzyme A Transporter (PAT) Family
2.A.1.25.1









The endoplasmic reticular/golgi acetyl-CoA:CoA antiporter 1, ACATN/ACATN1 (SLC33A1).  Allows acetylation of sialic acid residues in gangliosides and lysine residues in membrane proteins.  It is associated with neurodegenerative disorders such as sporadic amyotrophic laterial sclerosis (ALS) and Spastic Paraplegia 42, and it is essential for motor neuron viability (Hirabayashi et al. 2013).

Eukaryota
Metazoa
SLC33A1 of Homo sapiens
2.A.1.25.2









Cell wall degradation product (peptides and glycopeptides including N-acetylglucosaminyl β-1,4-anhydro-N-acetyl-muramyl-tripeptide) as well as penicillin derivative uptake porter, AmpG (Cheng and Park 2002).

Bacteria
Proteobacteria
AmpG of E. coli (P0AE16)
2.A.1.25.3









The AmpG peptidoglycan uptake porter; part of the peptidoglycan recycling pathway (Garcia and Dillard, 2008)
Bacteria
Proteobacteria
AmpG of Neisseria gonorrhoeae (Q5F6G0)
2.A.1.25.4









Major facilitator superfamily domain-containing protein 3
Eukaryota
Metazoa
Mfsd3 of Rattus norvegicus
2.A.1.25.5









Transporter of N-acetylglucosamine anhydrous N-acetylmuramyl peptides, AmpG (Kong et al. 2010).  Necessary for induction of β-lactam resistance (Zhang et al. 2010).

Bacteria
Proteobacteria
AmpG of Pseudomonas aeruginosa
2.A.1.26:  The Unknown Major Facilitator-2 (UMF2) Family
2.A.1.26.1









41.4 KDa Protein, YcaD
Bacteria
Proteobacteria
YcaD of E. coli
2.A.1.26.2









MFS porter, YfkF; possible drug exporter

Bacteria
Firmicutes
YfkF of Bacillus subtilis (O34929)
2.A.1.27:  The Phenyl Propionate Permease (PPP) Family
2.A.1.27.1









The phenylpropionate porter, HcaT (YfhS) (Díaz et al. 1998).

Bacteria
Proteobacteria
HcaT (YfhS) of E. coli
2.A.1.28:  The Feline Leukemia Virus Subgroup C Receptor (FLVCR) Family
2.A.1.28.1









Cell surface receptor (c-receptor) for anemia-inducing feline leukemia virus subgroup C (FLCVR); functions in haem export in haemopoietic cells (Latunde-Dada et al., 2006Khan and Quigley, 2011). May cause Diamond-Blackfan anemia when defective (Keel et al., 2008). Mutations of FLVCR1 in posterior column ataxia and retinitis pigmentosa result in the loss of heme export activity (Yanatori et al., 2012). Heme accumulation causes toxicity.  FLVCR1 is co-induced upon iron insufficiency in the placenta with the LDL recpetor-related protein 1 (LRP1) heme receptor, and these two proteins may be important for neonatal iron status (Cao et al. 2014).  It is required for erythroid and αβ-, CD4 and CD8 T- cell development (Philip et al. 2015).

Eukaryota
Metazoa
C-receptor of Homo sapiens
2.A.1.28.2









The MFS-Domain7 protein (516aa)
(the MFS-D7 mRNA is expressed in many human tissues, especially in lungs and testis).
Eukaryota
Metazoa
MFSD7 of Mus musculus
2.A.1.28.3









Unknown major facilitator

Bacteria
Actinobacteria
UMF of Coriobacterium glomerans (F2NBU7)
2.A.1.28.4









The Fowler syndrome-associated protein, feline leukemia virus subgroup C receptor-related protein 2, is a heme importer (Duffy et al., 2010).

Eukaryota
Metazoa
FLVC2 of Homo sapiens (Q9UPI3)
2.A.1.28.5









MFS porter

Bacteria
Spirochaetes
MFS porter of Leptospira biflexa (B0SL69)
2.A.1.28.6









Electrogenic DIRC2 (Disrupted in renal carcinoma 2) (glycosylated and proteolytically processed (Savalas et al., 2011)). Targeted to lysosomes via an N-terminal dileueine motif. 

Eukaryota
Metazoa
DIRC2 of Homo sapiens (Q96SL1)
2.A.1.28.7









Feline leukemia virus subgroup C receptor-related protein 1
Eukaryota
Metazoa
FLVCR1 of Felis catus
2.A.1.29:  The Unknown Major Facilitator-3 (UMF3) Family
2.A.1.29.1









Archaeal open reading frame
Archaea
Euryarchaeota
Orf of Archaeoglobus fulgidus
2.A.1.29.2









Archaeal open reading frame
Archaea
Crenarchaeota
Orf of Aeropyrum pernix
2.A.1.29.3









Bacterial unknown major facilitator

Bacteria
Actinobacteria
UMF3 member of Frankia sp. Eul1c (E3J3E7)
2.A.1.30:  The Putative Abietane Diterpenoid Transporter (ADT) Family
2.A.1.30.1









Putative abietane uptake permease (in gene cluster for degradation of abietane diterpenoids), DitE
Bacteria
Proteobacteria
DitE of Pseudomonas abietaniphila BKME-9
2.A.1.31:  The Nickel Resistance (Nre) Family
2.A.1.31.1









The Ni2+ efflux pump, NreB (Ni2+ inductible)
Bacteria
Proteobacteria
NreB of Achromobacter xylosoxidans plasmid pTOM
2.A.1.31.2









The Ni2+ resistance protein, NrsD
Bacteria
Cyanobacteria
NrsD of Synechocystis PCC6803
2.A.1.31.3









The unknown porter, YfiS

Bacteria
Firmicutes
YfiS of Bacillus subtilis (O31561)
2.A.1.31.4









Kurstakin/surfactin exporter of 417 aas (in B. subtilis) (Li et al. 2015).  This protein is an ortholog of the B subtilis protein (Li et al. 2015).
Bacteria
Firmicutes
KrsE of Bacillus cereus
2.A.1.31.5









Uncharacterized MFS porter of 455 aas

Eukaryota
Viridiplantae
UP of Chlamydomonas reinhardtii (Chlamydomonas smithii)
2.A.1.31.6









Uncharacterized MFS porter (residiues 1 - 450) with hydrophilic C-terminal protein kinase domain.  The protein is of 858 aas.

Eukaryota
Viridiplantae
UP of Chlamydomonas reinhardtii (Chlamydomonas smithii)
2.A.1.32:  The Putative Aromatic Compound/Drug Exporter (ACDE) Family
2.A.1.32.1









Putative aromatic compound/drug exporter. Enhances expression of the sigma X gene that functions to modify the cell envelope (Turner and Helmann, 2000). yitG is reported to be a mutator gene that inhibits transition base substitutions (Sasaki and Kurusu, 2004).

Bacteria
Firmicutes
YitG of Bacillus subtilis
2.A.1.32.2









Bacillibactin exporter, YmfE (199aas; 6TMSs) (Miethke et al., 2008) (resembles the 2nd half of YitG of B. subtilis (2.A.1.32.1). The sequence provided under acc# O31763 is only a fragment of the full length gene.
Bacteria
Firmicutes
YmfE of Bacillus subtilis (O31763)
2.A.1.32.3









Putative copper/multidrug efflux protein, YfmO.  The yfmPO operon is autoregulated by the MerR homologue, YfmP (a repressor). The copZA operon encodes CopA, a copper ATPase (TC# 3.A.3.5.18) which is induced by a copper dependent mechanism. Since a yfmP null mutant had poor copZA induction but elevated levels of the YfmO efflux pump, YfmO could catalyze copper efflux and be responsible for reduced copZA induction. Consistent with this model, a yfmP yfmO double mutant showed normal induction by copper (Gaballa et al. 2003).

Bacteria
Firmicutes
YfmO of Bacillus subtilis
2.A.1.33:  The Putative YqgE Transporter (YqgE; UMF4) Family
2.A.1.33.1









MFS homologue, YqgE. Co-transcribed with ftsI, encoding the peptidoglycan transpeptidase that crosslinks peptidoglycan strands, releasing free D-alanine. Possibly YqgE is a D-alanine uptake porter.

Bacteria
Firmicutes
YqgE of Bacillus subtilis (P54487)
2.A.1.33.2









UMF4 family member

Bacteria
Bacteroidetes/Chlorobi group
UMF4 family member form Bacteroides ovatus (A7LYG9)
2.A.1.33.3









UMF4 family member (encoded near an α-glucuronidase; GH31 family; divergently transcribed). 

Archaea
Crenarchaeota
UMF4 family member of Sulfolobus tokodaii (Q96XI6)
2.A.1.34:   The Sensor Kinase-MFS Fusion (SK-MFS) Family
2.A.1.34.1









Sensor kinase (N-terminal 400 residues)/MFS fusion protein. The N-terminal domain resembles the sensor kinase of 414 aas of Anaeromyxobacter sp. KJ (ACG71775).

Bacteria
Proteobacteria
Fusion protein of Bordetella pertussis (Q7VWI9)
2.A.1.35:  The Fosmidomycin Resistance (Fsr) Family
2.A.1.35.1









The fosmidomycin resistance (Fsr) protein (confers fosmidomycin, trimethoprim and carbonylcyanide m-chlorophenylhydrazone (CCCP) resistance)
Bacteria
Proteobacteria
Fsr of E. coli
2.A.1.35.2









The cationic microbial peptide resistance (RosA) protein
Bacteria
Proteobacteria
RosA of Yersinia enterocolitica
2.A.1.35.3









MFS transporter of 388 aas and 12 TMSs

Bacteria
Firmicutes
MFS porter of Sulfobacillus acidophilus
2.A.1.36:  The Acriflavin-sensitivity (YnfM) Family
2.A.1.36.1









The acriflavin-sensitivity protein, YnfM (increases sensitivity to acriflavin specifically).  Also exports arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
YnfM of E. coli
2.A.1.36.2









Hypothetical MFS carrier

Bacteria
Proteobacteria
MFS carrier of Serratia proteamaculans (A8GHT9)
2.A.1.36.3









Putative uncharacterized transporter YgaY

Bacteria
Proteobacteria
YgaY of Escherichia coli
2.A.1.36.4









MdrA.  Putative MDR transporter that may export cationic and hydrophobic compounds, Sco4007.  Regulated by a TetR-like repressor that binds drugs (Hayashi et al. 2013).

Bacteria
Actinobacteria
MdrA (Sco4007) of Streptomyces coelicolor
2.A.1.36.5









MFS carrier of 389 aas

Bacteria
Proteobacteria
MFS carrier of Rhizobium loti
2.A.1.37:  The Unknown Major Facilitator-4 (UMF4) Family
2.A.1.37.1









Unknown Major Facilitator-4 family member, UMF4A, of 396 aas and 12 TMSs.

Bacteria
Spirochaetes
UMF4A of Brachyspira pilosicoli
2.A.1.37.2









UMF4 family member of 399 aas and 12 TMSs, UMF4B.

Bacteria
Spirochaetes
UMF4B of Brachyspira murdochii
2.A.1.37.3









UMF4C of 407 aas and 12 TMSs.

Archaea
Euryarchaeota
UMF4C of Ferroplasma sp. 
2.A.1.37.4









UMF4D of 399 aas and 12 TMSs

Bacteria
Spirochaetes
UMF4D of Sphaerochaeta pleomorpha
2.A.1.37.5









UMF4E of 373 aas and 12 TMSs

Archaea
Crenarchaeota
UMF4E of Caldisphaera lagunensis
2.A.1.38:  The Enterobactin (Siderophore) Exporter (EntS) Family
2.A.1.38.1









The enterobactin (siderophore) exporter, EntS or YbdA (Bleuel et al., 2005).  May also export arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
EntS (YbdA) of E. coli
2.A.1.38.2









The putative siderophore exporter (DUF 894; Pfam 05977), VabS
Bacteria
Proteobacteria
VabS of Listonella anguillarum (Q0E7C5)
2.A.1.38.3









Enterobactin exporter, EntS (Crouch et al., 2008) (probably orthologous to 2.A.1.38.1).
Bacteria
Proteobacteria
EntS of Salmonella typhimurium
(Q8ZR35)
2.A.1.39:  The Vibrioferrin (Siderophore) Exporter (PrsC) Family
2.A.1.39.1









The vibrioferrin (siderophore) exporter, PrsC (Tanabe et al., 2003)
Bacteria
Proteobacteria
PrsC of Vibrio parahaemolyticus (BAC16546)
2.A.1.40:  Major Facilitator Superfamily Domain-containing Protein Family
2.A.1.40.1









Major facilitator superfamily domain-containing protein 5
Eukaryota
Metazoa
Mfsd5 of Danio rerio
2.A.1.40.2









Major facilitator superfamily domain-containing protein 5
Eukaryota
Metazoa
MFSD5 of Pongo abelii
2.A.1.40.3









Major facilitator superfamily domain-containing protein 5
Eukaryota
Metazoa
mfsd5 of Xenopus tropicalis
2.A.1.41:  The Putative Bacteriochlorophyll Delivery (BCD) Family
2.A.1.41.1









Putative pigment transporter (Young and Beatty, 1998)
Bacteria
Proteobacteria
LhaA of Rhodobacter capsulatus
2.A.1.41.2









Putative pigment transporter (Young and Beatty, 1998)
Bacteria
Proteobacteria
PucC of Rhodobacter capsulatus
2.A.1.41.3









Putative bacteriochlorophyll synthase
Bacteria
Proteobacteria
Bch2 of Rhodobacter capsulatus
2.A.1.42:  The Lysophospholipid Transporter (LplT) Family
2.A.1.42.1









The lysophospholipid transporter, LplT (Harvat et al., 2005)
Bacteria
Proteobacteria
LplT of E. coli (NP_417312)
2.A.1.42.2









The putative lysophospholipid transporter-2-acyl glycerophosphoethanolamine acyl transferase/acyl ACP synthetase (LplT-Pls-ACS) fusion protein (Harvat et al., 2005).
Bacteria
Proteobacteria
The fused LplT-PlsC-ACS of Bradyrhizobium japonicum (BAC47589)
2.A.1.43:  The Putative Magnetosome Permease (PMP) Family
2.A.1.43.1









The putative magnetosomal permease, MamH (Schubbe et al., 2003)
Bacteria
Proteobacteria
MamH of Magnetospirillum gryphiswaldense (Q6NE63)
2.A.1.43.2









The putative magnetosome (Fe?) permease fused to a C-terminal YedZ-like domain (von Rozycki et al., 2004). This protein has 649 aas and 18 TMSs with a C-terminal YedZ domain and is therefore in the YedZ superfamily.

Bacteria
Proteobacteria
PMP of Magnetospirillum magneticum (Q2W8K5)
2.A.1.44:  The L-Amino Acid Transporter-3 (LAT3) Family (also called the SLC43 family)
2.A.1.44.1









The L-amino acid transporter-3, LAT3 (transports neutral amino acids such as L-leucine, L-isoleucine, L-valine, and L-phenylalanine by a Na+-independent, electroneutral, facilitated diffusion process; also transports amino acid alcohols) (Prostate cancer up-regulated gene product)
Eukaryota
Metazoa
SLC43A1 of Homo sapiens
2.A.1.44.2









L-amino acid transporter-4 (LAT4) has the same specificity and is 57% identity to LAT3. Na+, Cl- and pH independent; not trans-stimulated; two kinetic components, a low affinity component sensitive to NEM, and a high affinity component insensitive to NEM. Found in the basolateral membrane of epithelial cells in the distal tubule and collecting duct of the kidney and the crypt cells in the intestine (Bodoy et al., 2005).
Eukaryota
Metazoa
SLC43A2 of Homo sapiens
2.A.1.44.3









solute carrier family 43, member 3
Eukaryota
Metazoa
SLC43A3 of Homo sapiens
2.A.1.45:  The 2,4-diacetylphloroglucinol (PHL) Exporter (PHL-E) Family
2.A.1.45.1









The 2,4-diacetylphloroglucinol resistance/general stress porter, PhlE (Abbas et al., 2004)
Bacteria
Proteobacteria
PhlE of Pseudomonas fluorescens (CAD65845)
2.A.1.46:  The Unknown Major Facilitator-5 (UMF5) Family
2.A.1.46.1









Probable transporter

Bacteria
Proteobacteria
Probable transporter of Bordetella pertussis (Q7W0Q7)
2.A.1.46.2









Putative transporter
Bacteria
Actinobacteria
Putative transporter of Tropheryma whipplei (Q83N16)
2.A.1.46.3









Putative drug resistance UMF5 family member

Eukaryota
Kinetoplastida
Putative MDR pump of Leishmania infantum
2.A.1.46.4









UMF15 family member

Archaea
Euryarchaeota
UMF5 homologue of Methanosphaerula palustris (B8GFY3)
2.A.1.46.5









Putative quinolone resistance protein

Bacteria
Firmicutes
MFS porter of Bacillus cereus (C2UR80)
2.A.1.46.6









UPF0226 protein YfcJ.  Catalyzes export of arabinose but not xylose (Koita and Rao 2012).

Bacteria
Proteobacteria
YfcJ of E. coli
2.A.1.46.7









UPF0226 protein, YhhS.  Exports arabinose but not xylose (Koita and Rao 2012).  Also may export the herbicide, glyphosate (Staub et al. 2012).

Bacteria
Proteobacteria
YhhS of E. coli
2.A.1.46.8









MFS carrier of 366 aa

Archaea
Crenarchaeota
MFS carrier of Sulfolobus solfataricus
2.A.1.46.9









Uncharacterized MFS porter of 430 aas

Archaea
Euryarchaeota
MFS porter of Halosimplex carlsbadense
2.A.1.47:  The Unknown Major Facilitator-6 (UMF6) Family
2.A.1.47.1









Putative transporter
Bacteria
Firmicutes
Putative transporter of Lactobacillus plantarum (NP_784357)
2.A.1.47.2









UMF6 family member

Bacteria
Firmicutes
MFS carrier of Streptococcus suis (A4VY05)
2.A.1.47.3









Possible antibiotic peptide exporter (encoded in an operon together with lantibiotic biosynthesis enzymes)

Bacteria
Firmicutes
UMF6 family member of Streptococcus pneumoniae (B2IRN2)
2.A.1.47.4









MFS permease of 408 aas

Bacteria
Firmicutes
MFS permease of Streptococcus pneumoniae
2.A.1.48:  The Vacuolar Basic Amino Acid Transporter (V-BAAT) Family
2.A.1.48.1









The vacuolar basic amino acid (histidine, lysine and arginine) transporter, Vba1 (catalyzes uptake into the vacuoles (equivalent to efflux from the cytoplasm)) (most similar to family 2.A.1.3; DHA2; 13-14 putative TMSs) (Shimazu et al., 2005)
Eukaryota
Fungi
Vba1 of Saccharomyces cerevisiae (NP_013806)
2.A.1.48.2









The vacuolar basic amino acid (Arg, Lys, His) transporter, Vba2 (Shimazu et al., 2005)
Eukaryota
Fungi
Vba2 of Saccharomyces cerevisiae (P38358)
2.A.1.48.3









Vacuolar G0 arrest protein, Fnx1; involved in amino acid (e.g., his, lys, ile, asn, etc) uptake into the vacuole (Chardwiriyapreecha et al., 2008).
Eukaryota
Fungi
Fnx1 of Schizosaccharomyces pombe (Q09752)
2.A.1.48.4









Vacuolar amino acid uptake system, Fnx2 (Chardiwiriyapreecha et al., 2008)
Eukaryota
Fungi
Fnx2 of Schizosaccharomyces pombe (O59726)
2.A.1.48.5









Vacuolar basic amino acid transporter 4
Eukaryota
Fungi
VBA4 of Saccharomyces cerevisiae S288c
2.A.1.49:  The Endosomal Spinster (Spinster) Family
2.A.1.49.1









The spinster protein, spin1 or spns1 gene product (involved in synaptic growth regulation; interacts with Bcl-2/Bcl-xL, affecting programmed cell death) (Nakano et al., 2001; Sanyal and Ramaswami, 2002; Yanagisawa et al., 2003).  Probably transports sphingosine-1-phosphate (Fukuhara et al. 2012).

Eukaryota
Metazoa
Spinster of Drosophila melanogaster (AAG43825)
2.A.1.49.2









The spinster homologue, Spin1 or Spns1 gene (interacts with Bc1-2/Bc1-XL to induce a caspase-independent autophagic cell death; may be required for embryogenesis) (Yanagisawa et al., 2003). Probable spingosine-1-phosphate (or sphingolipid) transporter (Nijnik et al. 2012).

Eukaryota
Metazoa
Spin1 of Homo sapiens (Q9H2V7)
2.A.1.49.3









Probable sphingosine-1-phosphate (or sphingolipid) transporter, spinster homologue 3 (by similarity).

Eukaryota
Viridiplantae
Spinster homologue 3 of Arabidopsis thaliana (F4IKF6)
2.A.1.49.4









Protein Spinster homolog 2 (Spns2 or protein two of hearts).  Transports sphingosine-1-P (S1P) and the immunomodulating agent, FTY720 (Hisano et al. 2011; Nijnik et al. 2012).  S1P is a secreted lipid mediator that functions in vascular development. In the yolk syncytial layer, Spns2 functions in S1P secretion, thereby regulating myocardial precursor migration (Kawahara et al. 2009).

Eukaryota
Metazoa
Spns2 of Danio rerio
2.A.1.49.5









Probable sphingosine-1-phosphate or sphingolipid transporter, Spinster homolog 1 (by similarity).

Eukaryota
Viridiplantae
At5g65687 of Arabidopsis thaliana
2.A.1.49.6









Sphingosine-1-phosphate/dehydroshpingosine-1-P transport protein, Spinster 2. Involved in immune development and lymphocyte trafficing (Nijnik et al. 2012; Fukuhara et al. 2012). 

Eukaryota
Metazoa
SPNS2 of Homo sapiens
2.A.1.49.7









Bacterial Spinster homologue; possible sphingosine-1-phosphate transporter (by similarity only).

Bacteria
Proteobacteria
Spinster homologue of Myxococcus xanthus
2.A.1.49.8









Bacterial spinster homologue.  Possible sphingosine-1-phosphate transporter (by similarity only).

Bacteria
Fibrobacteres/Acidobacteria group
Spinster homologue of Terriglobus saanensis
2.A.1.49.9









The cis, cis muconate transporter of 508 aas.

Eukaryota
Metazoa
MucK of Bombyx mori (Silk moth)
2.A.1.49.10









MFS multidrug exporter of 429 aas and 12 TMSs.  Exports capreomycin and ethidium bromide, and deletion mutants grow faster than wild type cells (Zhang et al. 2015).

Bacteria
Actinobacteria
MDR pump of Mycobacterium smegmatis
2.A.1.50:  The Proton Coupled Folate Transporter/Heme Carrier Protein (PCFT/HCP) Family
2.A.1.50.1









The apical intestinal and choroid plexus proton-coupled, high affinity folate transporter, the hereditary folate malabsorption protein, PCFT/HCP1 (Shin et al. 2010).  Also reported to mediate heme-iron uptake from the gut lumen with duodenal epithelial cells (Shayeghi et al., 2005; Latunde-Dada et al., 2006; Subramanian et al., 2008, Shin et al., 2012b), but it shows a higher affinity for folate than heme) (Qiu et al., 2006). Responsible for folate uptake by choroid plexus epithelial cells (Wollack et al., 2007) and placenta (Yasuda et al., 2008). The rat orthologue (Q5EBA8) catalyzes H+-dependent folate uptake in the intestine (Inoue et al., 2008). Responsible for the rare autosomal recessive disorder, hereditary folate malabsorption (Zhao and Goldman, 2007). PCFT/ICP1, when mutated, is the cause of Hereditary Folate Malabsorption in humans (Qiu et al., 2006; Shin et al., 2012). Evidence for a 12 TMS topology with a renetrant look between TMSs 2 and 3 has been presented (Zhao et al., 2010; Qiu et al., 2006; Zhao et al., 2011; Wilson et al. 2014).  Downregulated in Chronic Kidney Disease (CKD) in heart, liver, and brain causing malabsorption (Bukhari et al., 2011). An IGXXG motif in TMS5 is important for folate binding and a GXXXG motif is involved in dimerization (Zhao et al., 2012). Inhibited by bicarbonate, bisulfite, nitrite and other anions (Zhao et al. 2013).  Its role in antifolate cancer chemotherapy has been reviewed (Matherly et al. 2014). TMSs 3 and 6 may provide critical interfaces for formation of hPCFT oligomers, facilitated by the GXXXG motifs in TMS2 and TMS4 (Wilson et al. 2015).

Eukaryota
Metazoa
SLC46A1 of Homo sapiens
2.A.1.50.2









Thymic stromal cotransporter, TSCOT (Kim et al. 2000)
Eukaryota
Metazoa
SLC46A2 of Homo sapiens
2.A.1.50.3









solute carrier family 46, member 3
Eukaryota
Metazoa
SLC46A3 of Homo sapiens
2.A.1.51:  The Unknown Major Facilitator 7 (UMF7) Family
2.A.1.51.1









Putative permease
Bacteria
Proteobacteria
Putative transporter of Azoarcus sp. EbN1 (CAI06874)
2.A.1.51.2









YjiJ MFS porter, a member of the DUF2118 family in Pfam.

Bacteria
Proteobacteria
YjiJ of E. coli (D6IHN4)
2.A.1.51.3









MFS permease

Bacteria
Deinococcus-Thermus
MFS permease of Thermus thermophilus (F6DF77)
2.A.1.51.4









Uncharacterized MFS permease

Bacteria
Proteobacteria
UP of Pseudomonas aeruginosa
2.A.1.52:  The Glycerophhosphodiester Uptake (GlpU) Family
2.A.1.52.1









The putative permease, YihN (most like NarK and UhpC, 21% identity)
Bacteria
Proteobacteria
YihN of E. coli (P32135)
2.A.1.52.2









YqcE putative transporter

Bacteria
Proteobacteria
YqcE pf E. coli (F4TJX1)
2.A.1.52.3









MFS permease

Bacteria
Actinobacteria
MFS permease of Propionibacterium acnes
2.A.1.52.4









The glycerophosphodiester, glycerophosphocholine uptake porter, GlpU.  The cytoplasmic compound is hydrolyzed to α-glycerolphosphate and choline (Großhennig et al. 2013).

Bacteria
Tenericutes
GlpU of Mycoplasma pneumoniae
2.A.1.53:  The Proteobacterial Intraphagosomal Amino Acid Transporter (Pht) Family
2.A.1.53.1









The threonine uptake permease, PhtA (Sauer et al., 2005) (required for maximal growth in macrophages and Acanthamoeba castellanii)
Bacteria
Proteobacteria
PhtA of Legionella pneumophila (YP_094583)
2.A.1.53.2









The valine uptake permease, PhtJ (required for maximal growth in macrophages and Acanthamoeba castellanii) (Chen et al., 2008)

Bacteria
Proteobacteria
PhtJ of Legionella pneumophila (YP_095910)
2.A.1.53.3









The putative MFSDI transporter (463aas; 12 TMSs)

Eukaryota
Metazoa
MFSDI of Homo sapiens (A6NID9)
2.A.1.53.4









Uncharacterized protein of 575 aas and 14 TMSs.

Eukaryota
Bangiophyceae
UP of Cyanidioschyzon merolae
2.A.1.54:  The Unknown (Archaeal/Bacterial) Major Facilitator-9 (UMF9) Family
2.A.1.54.1









The archaeal uptake permease, MMP0835 (function unknown) (31% I, 49% S with PhtA)

Archaea
Euryarchaeota
MMP0835 of Methanococcus maripaludis (CAF30391)
2.A.1.54.2









UMF-9

Bacteria
Proteobacteria
UMF9 of Geobacter sulfurreducens (Q747F2)
2.A.1.55:  The Iron · Pyridine Thiocarboxylic Acid Transporter (PDTC-T) Family
2.A.1.55.1









The iron (Fe3+) · pyridine-2,6-bis(thiocarboxylic acid (PDTC)) uptake transporter, PdTE. Functions with the OMR, PdtK, 1.B.14.8.2 (most similar to 2.A.1.57.4).

Bacteria
Proteobacteria
PdtE of Pseudomonas putida (ABC8353)
2.A.1.56:  The 1,3-Dihydroxybenzene Transporter (DHB-T) Family
2.A.1.56.1









The 1,3-dihydroxybenzene (resorcinol) uptake permease, MFS_1 (Darley et al., 2007)
Bacteria
Proteobacteria
MFS_1 of Azoarcus anaerobius (YP_285101)
2.A.1.56.2









Uncharacterized protein of 405 aas and 12 TMSs.

Bacteria
Proteobacteria
UP of Bradyrhizobium japonicum
2.A.1.57:  The Ferripyochelin Transporter (FptX) Family
2.A.1.57.1









The Ferripyochelin uptake permease, FptX (Michel et al., 2007).  Also transports N-acetylglucosamine anhydrous N-acetylmuramyl peptides and is called AmpP or AmpGh1 (Kong et al. 2010).  However, it does not play a role in the induction of β-lactam resistance (Zhang et al. 2010).

Bacteria
Proteobacteria
FptX or AmpP of Pseudomonas aeruginosa (Q9HWG8)
2.A.1.57.2









The ferric rhizbactin 1021 uptake porter, RhtX (Cuív et al. 2004).

Bacteria
Proteobacteria
RhtX of Sinorhizobium meliloti
2.A.1.57.3









Putative iron chelate transporter of 467 aas

Bacteria
Proteobacteria
Uncharacterized protein of E. coli
2.A.1.57.4









Siderophore transporter, RhtX/FptX family

Bacteria
Proteobacteria
Siderophore transporter of Myxococcus xanthus
2.A.1.58:  The N-Acetylglucosamine Transporter (NAG-T) Family
2.A.1.58.1









The N-acetylglucosamine:H+ symporter, Ngt1 (Alvarez and Konopka, 2007)

Eukaryota
Fungi
Ngt1 of Candida albicans (Q5A7S4)
2.A.1.58.2









May contribute to coordination of muscle contraction as regulatory subunit of a nonessential potassium channel complex.  Subunit structure:  May form a complex with sup-9 and sup-10 where unc-93 and sup-10 act as regulatory subunits of the two pore potassium channel sup-9.

 

Eukaryota
Metazoa
Unc-93 of Caenorhabditis elegans (Q93380)
2.A.1.58.3









UNC93-like protein MFSD11 (Major facilitator superfamily domain-containing protein 11) (Protein ET)

Eukaryota
Metazoa
MFSD11 of Mus musculus
2.A.1.58.4









MFS permease of 467 aas

Eukaryota
Viridiplantae
MFS permease of Oryza sativa
2.A.1.58.5









Duf895 protein of 450 aas

Eukaryota
Fungi
Duf895 protein of Verticillium albo-atrum
2.A.1.58.6









MFS permease of 425 aas

Eukaryota
Dictyosteliida
MFS permease of Dictyostellium discoideum
2.A.1.59:  Unidentified Major Facilitator-10 (UMF10) Family (mostly from Archaea but some from bacteria)
2.A.1.59.1









UMF10a of unknown function, (COG2270).

Archaea
Euryarchaeota
UMF10a of Methanococcus aeolicus (A6UVW2)
2.A.1.59.2









UMF10b (in an operon with a sensor kinase/response regulator pair and an 8 TMS rhomboid protease)



 

Bacteria
Cyanobacteria
UMF10b of Nostoc punctiforme (B2JBG5)
2.A.1.59.3









MFS permease, AF1541

Archaea
Euryarchaeota
AF1541 of Archaeoglobus fulgidus (O28731)
2.A.1.59.4









MFS permease, LepA

Bacteria
Aquificae
LepA of Hydrogenivirga sp.128-5-R1-1 (A8UT57)
2.A.1.60:  The Rhizopine-related MocC (MocC) Family
2.A.1.60.1









The rhizopine related transporter, MocC (could either transport a precursor for rhizopine biosynthesis into bacteroids or the finished product from the bacteroids) (Murphy et al., 1993)
Bacteria
Proteobacteria
MocC of Sinorhizobium meliloti (Q07609)
2.A.1.60.2









Inner membrane protein YbjJ

Bacteria
Proteobacteria
YbjJ of Escherichia coli
2.A.1.60.3









The multidrug (quinolone; tetarcycline) resistance pump, TcrA (Chang et al. 2011).

Bacteria
Proteobacteria
TcrA of Stenotrophomonas maltophilia (F2WVP9)
2.A.1.61:  The Microcin C51 Immunity Protein (MccC) Family
2.A.1.61.1









The MccC microcin C51 immunity protein (exports the peptide-nucleotide 'Trojan horse' antibiotic) (Fomenko et al., 2003; Kazakov et al., 2007)
Bacteria
Proteobacteria
MccC of E. coli (Q83Y57)
2.A.1.62:  The Unidentified Major Facilitator-11 (UMF11) Family

Possibly involved in transport of amino acids and their derivatives.

2.A.1.62.1









The UMF11 homologue

Bacteria
Firmicutes
UMF11 of Staphylococcus aureus (A8YZ14)
2.A.1.62.2









Putative Macrolide efflux pump (P-MEP), possibly involved in transport of amino acids and their derivatives.

 

Bacteria
Fusobacteria
P-MEP of Fusobacterium sp. 7_1 (C3WVU9)
2.A.1.62.3









UMF11 (links UMF11 with UMF13)

Bacteria
Firmicutes
UMF11 of Bacillus clausii (Q5WGH2)
2.A.1.63:  The Unidentified Major Facilitator-12 (UMF12) Family
2.A.1.63.1









The UMF12 protein 

Archaea
Euryarchaeota
UMF12 of Methanosarcina barkeri (Q467Y6)
2.A.1.63.2









UMF12 Possible amino acid exporter

Archaea
Euryarchaeota
UMF12 of Methanosarcina mazei (Q8PRW9)
2.A.1.63.3









Possible nucleotide or oligonucleotide uptake porter, UMF12

Bacteria
Deinococcus-Thermus
UMF12 of Deinococcus radiodurans (Q9RXM0)    
2.A.1.63.4









MFS carrier

Eukaryota
Fungi
MFS carrier of Saccharomyces cerevisiae K7 (P47159)
2.A.1.64:  The Unidentified Major Facilitator-13 (UMF13) Family
2.A.1.64.1









The UMF13 protein

Bacteria
Firmicutes
UMF13 of Streptococcus thermophilus (Q5M4L1)
2.A.1.64.2









Uncharacterized protein RP255
Bacteria
Proteobacteria
RP255 of Rickettsia prowazekii
2.A.1.65:  The Unidentified Major Facilitator-14 (UMF14) Family
2.A.1.65.1









The putative MFS carrier, Sugar Baby (Sug, isoform D); has a hydrophilic domain between TMSs 3 and 4. Overexpression causes an increased lifespan by 17%.
Eukaryota
Metazoa
Sugar Baby of Drosophila melanogaster (Q7KUF9)
2.A.1.65.2









Unknown MFS homologue; e-6 with 2.A.1.5 family members; has a hydrophilic domain between TMSs 3 and 4.
Eukaryota
Metazoa
UMF14 of Culex quinquefasciatus (B0W435)
2.A.1.65.3









Unknown MFS homologue UMF14 ( 833 aas, 12 TMSs in a 3+9 arrangement )

Eukaryota
Metazoa
UMF14 of Anopheles gambiae (Q7Q0Z9)
2.A.1.65.4









Uncharacterized protein of 474 aas

Eukaryota
Metazoa
UP of Nematostella vectensis (Starlet sea anemone)
2.A.1.65.5









MFS porter

Eukaryota
Metazoa
MFS porter of Daphnia pulex (E9I268)
2.A.1.65.6









Macrophage MHC Class I receptor 2, Mmr2 or MFSD6

Eukaryota
Metazoa
Mmr2 of Mus musculus (Q8CBH5)
2.A.1.65.7









MFS porter

Eukaryota
Viridiplantae
MFS porter of Chlorella variablis (E1ZG13)
2.A.1.65.8









MFS permease

Bacteria
Firmicutes
MFS permease of Thermoanaerobacter tengcongensis (Q8R7B7)
2.A.1.65.9









Maltose permease
Bacteria
Firmicutes
MalA of Geobacillus stearothermophilus
2.A.1.65.10









Major facilitator superfamily domain-containing protein 6-like
Eukaryota
Metazoa
MFSD6L of Homo sapiens
2.A.1.65.11









Duplicated MFS permease (901 amino acyl residues; ~24 TMSs)

Eukaryota
Viridiplantae
Duplicated MFS permease of Chlamydomonas reinhardtii
2.A.1.66:  The Unidentified Major Facilitator-15 (UMF15) Family
2.A.1.66.1









MFS permease of unknown function (First half resembles 2.A.1.3.7 (e-11) and 2.A.1.15.3 (e-8)). Very likely to be a galactoside/galactose transporter; encoded within a gene cluster with β-galactosidase and galactose metabolic genes.

Archaea
Crenarchaeota
MFS permease of Thermofilum pendens (A1RW34)
2.A.1.66.2









Putative 4-hydroxybenzoate uptake transporter, MFS_1 (in an operon with 2,3-diketo-5-methylthiopentyl-1-phosphate enolase-phosphatase of the methionine salvage pathway), using S-adenyl methionine (SAM) as substrate. May transport SAM.

Bacteria
Spirochaetes
MFS1 of Leptospira interrogans (Q8F7L4)
2.A.1.66.3









UMF15 Homologue

Eukaryota
Bacillariophyta
UMF15 homologue of Thalassiosira pseudonana (B8BU21)
 
2.A.1.66.4









MFS transporter of 531 aas.  Present in the membrane of the organelle called the rhoptries which is involved in host invasion and hijacking host cell functions (Peter Bradley, personal communication).

Eukaryota
Apicomplexa
MFS porter of Toxoplasma gondii
2.A.1.66.5









MFS transporter of 428 aas.  Present in the membrane of the organelle called the rhoptries which is involved in host invasion and hijacking host cell functions (Peter Bradley, personal communication).

Eukaryota
Apicomplexa
Porter of Toxoplasma gondii
2.A.1.67:  The Unidentified Major Facilitator-16 (UMF16) Family
2.A.1.67.1









MFS permease of unknown function (second half distantly resembles the first half of 2.A.1.41.3/e value of 0.001)

Bacteria
Actinobacteria
UMF16 of Kribbella flavida (D2PP09)
2.A.1.67.2









MFS porter

Bacteria
Actinobacteria
MFS porter of Arthrobacter aurescens (A1R564)
2.A.1.67.3









MFS porter

Bacteria
Proteobacteria
MFS porter of Erwinia pyrifoliae (D0FNI7)
2.A.1.67.4









MFS porter of 402 aas and 12 TMSs.

Bacteria
Actinobacteria
MFS porter of Propionibacterium acnes (D1YEI1)
2.A.1.68:  The Glucose Transporter (GT) Family
2.A.1.68.1









The glucose transporter, OEOE_1574 does not transport fructose (Kim et al., 2011).

Bacteria
Firmicutes
OEOE_1574 of Oenococcus onei (Q04DP6)
2.A.1.69:  Unidentified Major Facilitator-17 (UMF17) Family
2.A.1.69.1









The UMF17A porter

Bacteria
Actinobacteria
UMF17A porter of Streptomyces coelicolor (Q9KZY0)
2.A.1.70:  Unidentified Major Facilitaor-18 (UMF18) Family
2.A.1.70.1









UMF18A

Bacteria
Actinobacteria
UMF18A of Streptomyces coelicolor (Q9L223)
2.A.1.70.2









UMF18B 

Bacteria
Actinobacteria
UMF18B of Saccharomonospora azurea (G4JJZ0)
2.A.1.70.3









UMF18C

Bacteria
Actinobacteria
UMF18C of Salinispora tropica (A4X2L1)
2.A.1.71:  The Valanimycin-resistance (Val-R) Family
2.A.1.71.1









The Valanimycin-resistance determinant, VlmF (probably a valanimycin:H  antiporter (Ma et al., 2000))

Bacteria
Actinobacteria
VlmF of Streptomyces viridifaciens (Q9LA76)
2.A.1.71.2









The UMF19a porter

Bacteria
Actinobacteria
UMF19a porter of Streptomyces coelicolor (Q93J85)
2.A.1.72:  The Unidentified Major Facilitator-20 (UMF20) Family
2.A.1.72.1









The UMF20A porter

Bacteria
Actinobacteria
UMF20A of Streptomyces coelicolor (Q9RL01)
2.A.1.73:  The Unidentified Major Facilitator-21 (UMF21) Family
2.A.1.73.1









The UMF21A porter

Bacteria
Actinobacteria
UMF21A porter of Streptomyces coelicolor (Q9L102)
2.A.1.74:  The Unidentified Major Facilitator-22 (UMF22) Family
2.A.1.74.1









UMF22a porter 

Bacteria
Actinobacteria
UMF22 porter of Streptomyces coelicolor (Q9S243)
2.A.1.75:  The Unidentified Major Faciilitator-23 (UMF23) Family
2.A.1.75.1









Probable transporter MCH1 (Monocarboxylate transporter homolog 1)
Eukaryota
Fungi
MCH1 of Saccharomyces cerevisiae
2.A.1.75.2









Eukaryota
Fungi
Mct of Coccidioides posadasii (E9CYW5)
2.A.1.75.3









Uncharacterized major facilitator, UMF23C

Eukaryota
Fungi
UMF23C of Candida albicans
2.A.1.75.4









Uncharacterized major facilitator UMF23D

Eukaryota
Heterolobosea
UMF23D of Naegleria gruberi
2.A.1.75.5









UMF23 permease of 572 aa

Eukaryota
Viridiplantae
UMF23 of Arabidopsis thaliana
2.A.1.76:  The Uncharacterized Major Facilitator 24 Family
2.A.1.76.1









Uncharacterized protein, UMF24A, a member of the Pfam family, MFS_Mycoplasma.

Eukaryota
Metazoa
UMF24A of Mycoplasma pneumoniae
2.A.1.76.2









Uncharacterized Mycoplama MFS carrier, UMF24B

Bacteria
Tenericutes
UMF24B of Mycoplasma capricolum
2.A.1.76.3









Uncharacterized MFS carrier, UMF24C

Bacteria
Firmicutes
UMF24C of Lactobacillus salivarius
2.A.1.76.4









Bacteria
Tenericutes
MFS porter of Mycoplasma galisepticum
2.A.1.76.5









Uncharacterized protein Mhp246

Bacteria
Tenericutes
Mhp246 of Mycoplasma hyopneumoniae
2.A.1.77:  Uncharacterized Major Facilitator-25 (UMF25) Family
2.A.1.77.1









Unknown Major Facilitator UMF25a

Bacteria
Planctomycetes
UMF25a of Rhodopirellula baltica
2.A.1.77.2









Unknown Major Facilitator, UMF25b

Bacteria
Planctomycetes
UMF25b of Planctomyces limnophilus
2.A.1.78:  The Uncharacterized Major Facilitator-26 (UMF26) Family
2.A.1.78.1









UMF26a of 416 aas and 12 TMSs.  Encoded by a gene that is adjacent to two ATP hydrolyzing subunits homologous to ABC proteins of the peptide transporters of TC family 3.A.1.5.

Bacteria
Chlamydiae/Verrucomicrobia group
UMF26a of Parachlamydia acanthaemoebae (F8KXQ8)
2.A.1.78.2









UMF26b of 419 aas and 12 TMSs

Bacteria
Chlamydiae/Verrucomicrobia group
UMF26b of Simkania negevensis (F8L9E4)
2.A.1.78.3









UMF26c of 457 aas and 12 TMSs

Bacteria
Planctomycetes
UMF26c of Phycisphaera mikurensis (I0II84)
2.A.1.78.4









UMF26d of 413 aas and 12 TMSs

Bacteria
Chlamydiae/Verrucomicrobia group
UMF26d of Verrucomicrobiae bacterium (B5JEI3)
2.A.1.79:  The Uncharacterized Major Facilitator-27 (UMF27) Family
2.A.1.79.1









MFS permease of 485 aas

Eukaryota
Bangiophyceae
MFS permease of Cyanidioschyzon merolae
2.A.1.80:  The Uncharacterized Major Facilitator-28 (UMF28) Family
2.A.1.80.1









Uncharacterized MFS permease of 515 aas

Eukaryota
Bangiophyceae
Putative peremease of Galdieria sulphuraria
2.A.1.81:  The Copper Uptake Porter (Cu-UP)
2.A.1.81.1









The probable Copper (Cu2+) uptake porter, CcoA of 405 aas and 12 TMSs.

Bacteria
Proteobacteria
CcoA of Rhodobacter capsulatus
2.A.1.81.2









Putative copper uptake porter, MFS_1 of 420 aas

Bacteria
Chloroflexi
MFS_1 of Chloroflexus aggregans
2.A.1.81.3









MFS permease of 403 aas.

Bacteria
Actinobacteria
MFSA permease of Corynebacterium glutamicum
2.A.1.81.4









MFS porter of 350 aas

Archaea
Thaumarchaeota
MFS porter of Candidatus Caldiarchaeum subterraneum
2.A.1.82:  The Plant Copper Uptake Porter (Pl-Cu-UP)
2.A.1.82.1









The barley copper uptake porter, CT-1 of 749 aas; nearly identical to the wheat orthologue (Li et al. 2013).

Eukaryota
Viridiplantae
CT-1 of Hordeum vulgare (F2CRE4)
2.A.1.82.2









The putative copper uptake porter, CT1, of 825 aas. The C-terminal domain of 300 aas is a DUF572 (COG5134) domain.

Eukaryota
Viridiplantae
CT1 of Ostreococcus tauri (Q010B9)
2.A.1.82.3









Synaptic vesicle 2-related protein (SV2-related protein), SVOP.  This protein localizes to neurotransmitter-containing vesicles and has a nucleotide binding site (Yao and Bajjalieh 2009). ATP, GTP and NAD show binding affinities with the highest affinity for NAD, in contrast to SV2 (TC# 2.A.1.22.1), which binds both NAD and ATP with equal affinity.

Eukaryota
Metazoa
Sv2p of Mus musculus
2.A.1.82.4









Niacin uptake porter NiaP (Jeanguenin et al. 2012)

Bacteria
Firmicutes
YceI of Bacillus subtilis (O34691)
2.A.1.82.5









Uncharacterized MFS protein of 460 aas

Eukaryota
Viridiplantae
UP of Volvox carteri (Green alga)
2.A.1.83.1









MFS porter; possibly a 1-arseno-3-phosphoglycerate exporter.  Present in an operon concerned with arsenic resistance, possibly encoding the enzymes and transporters of a new pathway of arsenic biotransformation.  The adjacent gene encodes a 3-phosphoglycerate dehydrogenase homologue that could form the presumed substrate of the MFS porter which could be expelled from the cell (Barry Rosen personal communication.

Bacteria
Proteobacteria
MFS porter of Aliivibrio (Vibrio) salmonicida
2.A.1.83.2









Putative 1-arseno-3-phosphoglycerate exporter, MFS-83.

Bacteria
Proteobacteria
MFS-83 of Ferrimonas balearica
2.A.1.83.3









Putative 1-arseno-3-phosphoglycerate exporter of 460 aas (see 2.A.1.83.1).

Eukaryota
Phaeophyceae
MFS-83 of Ectocarpus siliculosus (Brown alga
2.A.1.84.1









Putative MFS permease of 467 aas and 12 TMSs

Bacteria
Spirochaetes
MFS permease of Treponema denticola
2.A.1.84.2









Uncharacterized protein of 435 aas and 12 TMSs.

Bacteria
Actinobacteria
UP of Slackia heliotrinireducens (Peptococcus heliotrinreducens)
2.A.1.84.3









Uncharacterized protein

Bacteria
Actinobacteria
UP of Streptosporangium roseum