TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameOrganismal TypeExample
3.A.1.1:  The Carbohydrate Uptake Transporter-1 (CUT1) Family
3.A.1.1.1









Maltooligosaccharide porter. The 3-D structure has been reported by Oldham et al. (2007). An altering access mechanism has been suggested for the maltose transporter resulting from rigid-body rotations (Khare et al., 2009). Bordignon et al. (2010) and Schneider et al. (2012) have reviewed the extensive knowledge available on MalEFGK, its mode of action and its regulatory interactions.  The transporter sequesters the MalT transcriptional activator at the cytoplasmic surface of the membrane in the absence of the transport substrate (Richet et al. 2012).

Proteobacteria

MalEFGK of E. coli
MalE (receptor [R])
MalF (membrane [M])
MalG (membrane [M])
MalK (cytoplasmic [C])
3.A.1.1.2









The putative arabinogalactan oligomer porter, GanOPQ (MalEFG) The energizing ATPase is probably MsmX (see 3.A.1.1.26)

Bacteria

GanOPG of Bacillus subtilis
YufK or GanO (R) (O07009)
YufL or GanP (M) (O32261)
YufM or GanQ (M) (O07011) MsmX (C) (see 3.A.1.1.26)
3.A.1.1.3









Glycerol-phosphate porter. Transports both glycerol-3-P and glycerol-3-P diesters including glycerophosphocholine but not glycerol-2-P (Yang et al. 2009; Wuttge et al. 2012).  UgpB (the receptor) binds glycerol 3-P with high affinity, but not glycerol 2-P (Wuttge et al. 2012).  UgpB (the receptor) binds glycerol 3-P with high affinity, but not glycerol 2-P (Wuttge et al. 2012).

Proteobacteria

UgpABCE of E. coli
UgpB (R)
UgpA (M)
UgpE (M)
UgpC (C)
3.A.1.1.4









Lactose porter
Proteobacteria
LacEFGK of Agrobacterium radiobacter
LacE (R)
LacF (M)
LacG (M)
LacK (C)
3.A.1.1.5









Hexitol (glucitol; mannitol) porter
Proteobacteria
SmoEFGK of Rhodobacter sphaeroides
SmoE (R)
SmoF (M)
SmoG (M)
SmoK (C)
3.A.1.1.6









Cyclodextrin porter
Proteobacteria
CymDEFG of Klebsiella oxytoca
CymE (R)
CymF (M)
CymG (M)
CymD (C)
3.A.1.1.7









Maltose/trehalose porter
Euryarchaeota
MalEFGK of Thermococcus litoralis
MalE (R)
MalF (M)
MalG (M)
MalK (C) (not sequenced)
3.A.1.1.8









Sucrose/maltose/trehalose porter (sucrose-inducible)
Proteobacteria
AglEFGK of Sinorhizobium meliloti
AglE (R)
AglF (M)
AglG (M)
AglK (C)
3.A.1.1.9









The oligosaccharide (glucuronate-linked to a xylo-oligosaccharide) ABC uptake porter, GuoEFGK in AguEFGK. GuoE binds with high affinity a four sugar aldotetrouronic
acid [2-O-α-(4-O-methyl-α-D-glucuronosyl)-xylotriose] (Shulami et al., 1999; S.Shulami, personal communication)

Bacteria

GuoEFGK of Geobacillus stearothermophilus
AguE or GuoE (R) (C9RT46)
AguF or GuoF (M) (Q09LY7)
AguG or GuoG (M) (Q09LY6)
AguK or GuoK (C) (not identified)
3.A.1.1.10









Alginate (MW 27,000 Da) (and Alginate oligosaccharides) uptake porter. Sphingomonas species A1 is a 'pit-forming' bacterium that directly incorporates alginate into its cytoplasm through a pit-dependent transport system, termed a 'superchannel' (Murata et al., 2008). The pit is a novel organ acquired through the fluidity and reconstitution of cell surface molecules, and through cooperation with the transport machinery in the cells. It confers upon bacterial cells a more efficient way to secure and assimilate macromolecules (Murata et al., 2008).

Proteobacteria
AlgSM1M2Q1Q2 of Sphingomonas sp.A1
AlgS (C)
AlgM1 (M)
AlgM2 (M)
AlgQ1 (R)
AlgQ2 (R)
3.A.1.1.11









Saturated and unsaturated oligogalacturonide transporter, TogMNAB (transports di- to tetrasaccharide pectin degradation products which consist of D-galacuronate, sometimes with 4-deoxy-L-threo-5-hexosulose uronate at the reducing end of the oligosaccharide) (Hugouvieux-Cotte-Pattat et al. 2001). Regulated by pectin utilization regulator KdgR (Rodionov et al. 2004)

Proteobacteria

Oligogalacturonide transporter TogMNAB of Erwinia chrysanthemi
TogM (M)
TogN (M)
TogA (C)
TogB (R)
3.A.1.1.12









Palatinose (isomaltulose; 6-O-α-D-glucopyranosyl-D-fructose) uptake porter
Proteobacteria
PalEFGK of Erwinia rhapontici
PalE (R)
PalF (M)
PalG (M)
PalK (C)
3.A.1.1.13









Glucose, mannose, galactose porter
Crenarchaeota
GlcSTUV of Sulfolobus solfataricus
GlcS (R)
GlcT (M)
GlcU (M)
GlcV (C)
3.A.1.1.14









Arabinose, fructose, xylose porter
Crenarchaeota
AraSTUV of Sulfolobus solfataricus
AraS (R)
AraT (M)
AraU (M)
AraV (C)
3.A.1.1.15









Trehalose porter
Crenarchaeota
TreSTUV of Sulfolobus solfataricus
TreS (R)
TreT (M)
TreU (M)
TreV (C)
3.A.1.1.16









Maltooligosaccharide porter (Maltose is not a substrate, but maltotriose is.)
Euryarchaeota
PF1933, 1936, 1937, 1938 of Pyrococcus furiosus
PF1938 (R)
PF1937 (M)
PF1936 (M)
PF1933 (C)
3.A.1.1.17









Trehalose/maltose/sucrose porter (trehalose inducible)
Proteobacteria
ThuEFGK of Sinorhizobium meliloti
ThuE (R)
ThuF (M)
ThuG (M)
ThuK (C)
3.A.1.1.18









N-Acetylglucosamine/N,N'-diacetyl chitobiose porter (NgcK (C) not identified)
Actinobacteria
NgcEFG of Streptomyces olivaceoviridis
NgcE (R)
NgcF (M)
NgcG (M)
3.A.1.1.19









Platinose (isomaltulose) (6-O-α-D-glucopyranosyl-D-fructofuranose) porter
Proteobacteria
PalEFGK of Agrobacterium tumefaciens
PalE (R)
PalF (M)
PalG (M)
PalK (C)
3.A.1.1.20









The fructooligosaccharide porter, MsmEFGK (Barrangou et al., 2003)
Bacteria
MsmEFGK of Lactobacillus acidophilus
MsmE (R) AAO21856
MsmF (M) AAO21857
MsmG (M) AAO21858
MsmK (C) AAO21860
3.A.1.1.21









The xylobiose porter; BxlEFG(K) (Tsujibo et al., 2004)
Bacteria
BxlEFGK of Streptomyces thermoviolaceus
BxlE (R) CAB88161
BxlF (M) CAB88162
BxlG (M) CAB88163
BxlK (C) Unknown
3.A.1.1.22









The maltose, maltotriose, mannotetraose (MalE1)/maltose, maltotriose, trehalose (MalE2) porter (Nanavati et al., 2005). For MalG1 (823aas) and MalG2 (833aas), the C-terminal transmembrane domain with 6 putative TMSs is preceded by a single N-terminal TMS and a large (600 residue) hydrophilic region showing sequence similarity to MLP1 and 2 (9.A.14; e-12 & e-7) as well as other proteins.

Thermotogae
MalE1E2FGK of Thermotoga maritima
MalE1 (R) (binds maltose, maltotriose and mannotetraose) (AAD36279)
MalE2 (R) (binds maltose, maltotriose and trehalose) (AAD36901)
MalF1 (M) (AAD36278)
MalG1 (M) (AAD36277)
[MalG2 (M) (AAD36899]
MalK (C) (AAD36351)
3.A.1.1.23









The cellobiose/cellotriose (and possibly higher cellooligonucleosides), CebEFGMsiK [MsiK functions to energize several ABC transporters including those for maltose/maltotriose and trehalose] (Schlösser et al., 1997, Schlösser et al., 1999)

Bacteria

CebEFGMsiK of Streptomyces reticuli
CebE (R) (CAB46342)
CebF (M) (CAB46343)
CebG (M) (CAB46344)
MsiK (CAA70125)
3.A.1.1.24









The glucose/mannose porter TTC0326-8 plus MalK1 (ABC protein, shared with 3.A.1.1.25) (Chevance et al., 2006).
Bacteria
TTC0326-8 MalK1 of Thermus thermophilus
TTC0326 (M) - Q72KX4
TTC0327 (M) - Q72KX3
TTC0328 (R) - Q72KX2
MalK1 or TTC0211 (C) - Q72L52
3.A.1.1.25









The trehalose/maltose/sucrose/palatinose porter (TTC1627-9) plus MalK1 (ABC protein, shared with 3.A.1.1.24) (Chevance et al., 2006).
Bacteria
TTC1627-9 + MalK1 of Thermus thermophilus
TTC1627 (R) (Q72H68)
TTC1628 (M) (Q72H67)
TTC1629 (M) (Q72H66)
MalK1 (TTC0211) (C) (Q72L52)
3.A.1.1.26









The maltose porter, MdxEFG and MsmX (Ferreira and Sá-Nogueira, 2010)

Bacteria

The maltose porter of Bacillus subtilis, MalEFG/MsmX.
MalE (R) - O06989
MalF (M) - O06990
MalG (M) - O06991
MsmX (C) - P94360
3.A.1.1.27









Maltose/Maltotriose/maltodextrin (up to 7 glucose units) transporters MalXFGK (MsmK (3.A.1.1.28) can probably substitute for MalK; Webb et al., 2008).

Bacteria

MalXFGK of Streptococcus mutans:
MalX (R) (Q8DT28)
MalF (M) (Q8DT27)
MalG (M) (Q8DT26)
MalK (C) (Q8DT25)
3.A.1.1.28









The raffinose/stachyose transporter, MsmEFGK (MalK (3.A.1.1.27) can probably substitute for MsmK; Webb et al., 2008).

Bacteria

MsmEFGK of Streptococcus mutans:
MsmE (R) (Q00749)
MsmF (M) (Q00750)
MsmG (M) (Q00751)
MsmK (C) (Q00752)
3.A.1.1.29









Aldouronate transporter, LplA,B,C (Chow et al., 2007)
Bacteria
LplABC of Paenibacillus sp. JDR-2:
LplA (R)(A9QDR6)
LplB (M)(A9QDR7)
YtcP (M)(A9QDR8)
LplC - not identified
3.A.1.1.30









Glucose porter, GtsABCD (del Castillo et al., 2008).

Bacteria

The glucose porter of Pseudomonas putida, GtsABCD:
GtsA (R) (Q88P38)
GtsB (M) (Q88P37)
GtsC (M) (Q88P36)
GtsD (C) (Q88P35)
3.A.1.1.31









The trehalose-recycling ABC transporter, LpqY-SugA-SugB-SugC (essential for virulence) (Kalscheuer et al., 2010).

Bacteria

LpqY-SugA-SugB-SugC of Mycobacterium tuberculosis
LpqY (R) (Q7D8J9)
SugA (M) (O50452)
SugB (M) (O50453)
SugC (C) (O50454)  
3.A.1.1.32









The glucosylglycerol uptake transporter (functions in osmoprotection and also transports sucrose and trehalose (Mikkat and Hagemann, 2000) (most similar to 3.A.1.1.8).
Bacteria
GgtABCD of Synechocystis sp. strain PCC6803
GgtA (C) (Q55035)
GgtB (R) (Q55471)
GtC (M) (Q55472)
GgTD (M) (Q55473)
3.A.1.1.33









The N,N'-diacetylchitobiose uptake transporter, DasABC/MsiK (MsiK energizes several ABC transporters (see 3.A.1.1.23)) (Saito et al., 2008)

Bacteria

DasABC MsiK of Streptomyces coelicolor
DasA (R) (Q8KN19)
DasB (M) (Q8KN18)
DasC (M) (Q8KN17)
MsiK (C) (Q9L0Q1)
3.A.1.1.34









The arabinosaccharide transporter AraNPQMsmX. Transports α-1,5-arabinooligosaccharides, at least up to four L-arabinosyl units; the key transporter for α-1,5-arabinotriose and α-1,5-arabinotetraose, but not for α-1,5-arabinobiose which is transported by AraE. MsmX is also used by the MdxEFG-MsmX system (3.A.1.1.36) (Ferreira and Sá-Nogueira, 2010). 

Bacteria

AraNPQ-MsmX of Bacillus subtilis 
AraN (R) (P94528) 
AraP (M) (P94529)
AraQ (M) (P94530)
MsmX (C) (P94360) 
3.A.1.1.35









Glycerol uptake porter, GlpSTPQV (Ding et al., 2012).

  α-proteobacteria

GlpSTPQV of Rhizobium leguminosarum 
GlpS (C) (G3LHY8)
GlpT (C) (G3LHY9)
GlpP (M) (G3LHZ0)
GlpQ (M) (G3LHZ1)
GlpV (R) (G3LHZ3) 
3.A.1.1.36









Putative transport system

Actinobacteria



Q93J94 (R)
Q93J93 (M)
Q93J92 (M)
Q9L0Q1 (C?)
3.A.1.1.37









Predicted arabinoside porter. Regulated by arabinose-responsive regulator AraR (Rodionova et al. 2012).

Thermotogae

AraEFG of Thermotoga maritima
AraE (R) (TM0277) -
AraF (M) (TM0278) Q9WYB4
AraG (M) (TM0279) Q9WYB5
3.A.1.1.38









Inositol phosphate porter (D.A. Rodionov, personal communication). Binds inositol phosphate with low Kd and inositol with less affinity.

Thermotogae

InoEFGK of Thermotoga maritima
InoE (R) TM0418 (Q9WYP9)
InoF (M) TM0419 (Q9WYQ0)
InoG (M) TM0420 (Q9WYQ1)
InoK (C) TM0421 (Q9WYQ2)
3.A.1.1.39









Alpha-1,4-digalacturonate porter (Nanavati et al., 2006). Regulated by pectin utilization regulon UxaR (Rodionova et al. 2012).

Thermotogae

AguEFG of Thermotoga maritima
AguE (R) (TM0432) (Q9WYR3)
AguF (M) (TM0431) (Q9WYR2)
AguG (M) (TM0430) (Q9WYR1)
3.A.1.1.40









Predicted chitobiose porter. Regulated by chitobiose-responsive regulator ChiR (Kazanov et al., 2012).

Thermotogae

ChiEFG of Thermotoga maritima
ChiE (R) (TM0810) (Q9WZR7)
ChiF (M) (TM0811) (Q9WZR8)
ChiG (C) (TM0812) (Q9WZR9)
3.A.1.1.41









Trehalose porter. Also binds sucrose (Boucher and Noll, 2011). Induced by glucose and trehalose. Directly regulated by trehalose-responsive regulator TreR (Kazanov et al., 2012).

Thermotogae

TreG (M) (ThemaDRAFT_1378) G4FGN6 TreF (M) (ThemaDRAFT_1379) G4FGN7 TreE (R) (ThemaDRAFT_1380) G4FGN8
3.A.1.2:  The Carbohydrate Uptake Transporter-2 (CUT2) Family
3.A.1.2.1









Ribose porter (RbsC has 10 TMSs with N- and C-termini in the cytoplasm (Stewart and Hermodson, 2003))

Proteobacteria

RbsABC of E. coli
RbsA (C)
RbsB (R)
RbsC (M)
3.A.1.2.2









Arabinose porter
Proteobacteria
AraFGH of E. coli
AraF (R)
AraG (C)
AraH (M)
3.A.1.2.3









Galactose/glucose (methyl galactoside) porter
Proteobacteria
MglABC of E. coli
MglA (C)
MglB (R)
MglC (M)
3.A.1.2.4









Xylose porter
Proteobacteria
XylFGH of E. coli
XylF (R)
XylG (C)
XylH (M)
3.A.1.2.5









Multiple sugar (arabinose, xylose, galactose, glucose, fucose) putative porter
Proteobacteria
ChvE, GguAB of Agrobacterium tumefaciens
ChvE (R)
GguA (C)
GguB (M)
3.A.1.2.6









D-allose porter
Proteobacteria
AlsABC of E. coli
AlsB (R)
AlsA (C)
AlsC (M)
3.A.1.2.7









Fructose/mannose/ribose porter
Proteobacteria
FrcABC of Sinorhizobium meliloti
FrcA (C)
FrcB (R)
FrcC (M)
3.A.1.2.8









AI2 autoinducer porter (Taga et al., 2001, 2003)
Proteobacteria
LsrACDB of E. coli
LsrB (R) AAC74589
LsrA (C) AAC74586
LsrC (M) AAC74587
LsrD (M) AAC74588
3.A.1.2.9









Rhamnose porter (Richardson et al., 2004) (Transport activity is dependent on rhamnokinase (RhaK; AAQ92412) activity (Richardson and Oresnik, 2007) This could be an example of group translocation!)
Proteobacteria
RhaSTP of Rhizobium leguminosarum bv. trifolii
RhaS (R) AAQ92407
RhaT (C) AAQ92408
RhaP (M) AAQ92409
3.A.1.2.10









The purine nucleoside permease (probably transports guanosine, adenosine, 2'-deoxyguanosine, inosine and xanthosine with decreasing affinity in this order) (Deka et al., 2006)
Spirochaetes
PnrA-E of Treponema pallidum
PnrA (R) (TmpC; Tp0319) (P29724)
PnrB (?51 aas; 1 TMS; Tp0320) (O83340)
PnrC (C) (533 aas; duplicated; Tp0321) (NP_218761)
PnrD (M) (400 aas; 10 TMSs; Tp0322) (NP_218762)
PnrE (M) (316 aas; 10 TMSs; Tp0323) (NP_218763)
3.A.1.2.11









The erythritol permease, EryEFG (Geddes et al., 2010) (probably orthologous to 3.A.1.2.16)

Bacteria

EryEFG of Sinorhizobium meliloti
EryE (C) (CAC48737)
EryF (M) (CAC48738)
EryG (R) (CAC48735)
3.A.1.2.12









The (deoxy)ribonucleoside permease; probably takes up all deoxy- and ribonucleosides (cytidine, uridine, adenosine and toxic analogues, fluorocytidine and fluorouridine tested), but not ribose or nucleobases (Webb and Hosie, 2006)
Bacteria
RnsABCD of Streptococcus mutans
RnsA (R) (AAN58814)
RnsB (C) (AAN58813)
RnsC (M) (AAN58812)
RnsD (M) (AAN58811)
3.A.1.2.13









The probable autoinducer 2 (AI2) uptake porter (Shao et al., 2007) (50-70% identical to RbsABC of E. coli; TC# 3.A.1.2.1)

Bacteria

RbsABC of Aggregatibacter actinomycetemcomitans (Actinobacillus succinogens)
RbsA(C) (A6VKS8)
RbsB(R) (A6VKT0)
RbsC(M) (A6VKS9)
3.A.1.2.14









Putative L-arabinose porter (Rodionov et al. 2010).

Proteobacteria

AraUVWZ of Shewanella oneidensis
AraU (R) (Q0HIQ8)
AraV (C-C) (Q0HIQ7)
AraW (M; 10 TMSs) (Q0HIQ6)
AraZ (M; 9 TMSs) (Q0HIQ5)
3.A.1.2.15









The putative xylitol uptake porter, XltABC (Rodionov et al., 2010)

Proteobacteria

XltABC of Shewanella pealeana
XltA (C) (A8H4W7)
XltB (M; 9 TMSs) (A8H4W6)
XltC (R) (A8H4W5)
3.A.1.2.16









The erythritol uptake permease, EryEFG (Yost et al., 2006) (probably orthologous to 3.A.1.2.11)

Bacteria

EryEFG of Rhizobium leguminosarum
EryE (C) (Q1M4Q7)
EryF (M) (Q1M4Q8)
EryG (R) (Q1M4Q9)
3.A.1.2.17









General nucleoside uptake porter, NupABC/BmpA (transports all common nucleosides as well as 5-fluorocytidine, inosine, deoxyuridine and xanthosine) (Martinussen et al., 2010) (Most similar to 3.A.1.2.12). NupA is 506aas with two ABC (C) domains. NupB has 8 predicted TMSs, NupC has 9 or 10 predicted TMSs in a 4 + 1 (or2) + 4 arrangement.

Bacteria

NupABC/BmpA of Lactococcus lactis
BmpA (R) (D2BKA1)
NupA (C) (A2RKA7)
NupB (M) (A2RKA6)
NupC (M) (A2RKA5)
3.A.1.2.18









Xylose porter (Nanavati et al. 2006). Regulated by xylose-responsive regulator XylR (Kazanov et al., 2012).

Thermotogae

XylFEK of Thermotoga maritima
XylF (M) (TM0112) (Q9WXW7)
XylE (R) (TM0114) (Q9WXW9)
XylK (C) (TM0115) (Q9WXW0)
3.A.1.2.19









D-ribose porter (Nanavati et al., 2006). Induced by ribose (Conners et al., 2005).

Thermotogae

RbsABC of Thermotoga maritima
RbsA (C) (TM0956) (Q9X051)
RbsB (R) (TM0958) (Q9X053)
RbsC (M) (TM0955) (Q9X050)  
3.A.1.2.20









Glucose porter. Also bind xylose (Boucher and Noll 2011). Induced by glucose (Frock et al. 2012). Directly regulated by glucose-responsive regulator GluR (Kazanov et al., 2012).

Thermotogae

GluEFK of Thermotoga maritima
GluE (C) (ThemaDRAFT_1377) (G4FGN5)
GluF (C) (ThemaDRAFT_1376) (G4FGN4)
GluK (C) (ThemaDRAFT_1375) (G4FGN3)  
3.A.1.2.21









The myoinositol (high affinity)/ D-ribose (low affinity) transporter IatP/IatA/IbpA. The structure of IbpA with myoinositol bound has been solved (Herrou and Crosson 2013).

α-Proteobacteria

IatP/IatA/IbpA of Caulobacter crescentus
IatP (M) (B8H230)
IatA (C) (B8H229)
IbpA (R) (B8H228)
3.A.1.3:  The Polar Amino Acid Uptake Transporter (PAAT) Family
3.A.1.3.1









Histidine; arginine/lysine/ornithine porter
Proteobacteria
HisJ (histidine receptor)-ArgT (arg/lys/orn receptor)-HisMPQ of Salmonella typhimurium
HisJ (R)
ArgT (R)
HisM (M)
HisQ (M)
HisP (C)
3.A.1.3.2









Glutamine porter
Proteobacteria
GlnHPQ of E. coli
GlnH (R)
GlnP (M)
GlnQ (C)
3.A.1.3.3









Arginine porter
Proteobacteria
ArtI (arginine receptor #1)/ArtJ (arginine receptor #2)-ArtMQP of E. coli
ArtP (C)
ArtQ (M)
ArtM (M)
ArtJ (R)
ArtI (R)
3.A.1.3.4









Glutamate/aspartate porter
Proteobacteria
GltIJKL of E. coli
GltI (R)
GltJ (M)
GltK (M)
GltL (C)
3.A.1.3.5









Octopine porter
Proteobacteria
OccQMPT of Agrobacterium tumefaciens
OccT (R)
OccQ (M)
OccM (M)
OccP (C)
3.A.1.3.6









Nopaline porter
Proteobacteria
NocQMPT of Agrobacterium tumefaciens
NocT (R)
NocQ (M)
NocM (M)
NocP (C)
3.A.1.3.7









Glutamate/glutamine/aspartate/asparagine porter
Proteobacteria
BztABCD of Rhodobacter capsulatus
BztA (R)
BztB (M)
BztC (M)
BztD (CC)
3.A.1.3.8









General L-amino acid porter; transports basic and acidic amino acids preferentially, but also transports aliphatic amino acids (catalyzes both uptake and efflux) (Prell et al. 2009; Hosie et al. 2002Hosie et al. 2002).

Proteobacteria

AapJQMP of Rhizobium leguminosarum
AapJ (R)
AapQ (M)
AapM (M)
AapP (C)
3.A.1.3.9









Glutamate porter
Actinobacteria
GluABCD of Corynebacterium glutamicum
GluA (C)
GluB (R)
GluC (M)
GluD (M)
3.A.1.3.10









Cystine/diaminopimelate
Proteobacteria
Cys/Dap porter of E. coli
CysX (R)
CysY (M)
CysZ (C)
3.A.1.3.11









Arginine/ornithine (but not lysine) porter
Proteobacteria
AotJQMP of Pseudomonas aeruginosa
AotJ (R)
AotQ (M)
AotM (M)
AotP (C)
3.A.1.3.12









Arginine/lysine/histidine/glutamine porter
Cyanobacteria
BgtAB of Synechocystis PCC6803
BgtA (C)
BgtB (R-M)
3.A.1.3.13









Uptake system for L-cystine (Km=2.5 μM), L-cystathionine, L-djenkolate, and S-methyl-L-cysteine (Burguière et al., 2004, Burguière et al., 2005)

Firmicutes
TcyJKLMN (YtmJKLMN) of Bacillus subtilis
TcyJ (R) (NP_390816)
TcyK (R) (O34852)
TcyL (M) (O34315)
TcyM (M) (O34931)
TcyN (C) (O34900)
3.A.1.3.14









Uptake system for L-cystine (Burguière et al., 2004)

Firmicutes
TcyABC (YckKJI) of Bacillus subtilis
TcyA (R) (P42199)
TcyB (M) (P42200)
TcyC (C) (P39456)
3.A.1.3.15









Putative uptake system for arginine, YqiXYZ (Sekowska et al., 2001)

Bacteria

YqiXYZ of Bacillus subtilis
YqiX (R) (P54535)
YqiY (M) (P54536)
YqiZ (C) (P54537)
3.A.1.3.16









Uptake system for glutamate and aspartate (Leon-Kempis et al., 2006)
Proteobacteria
PEB1 transport system Campylobacter jejuni
PEB1a (R) (Q0P9X8)
PED1b (M) (A1VZQ3)
PEB1c (C) (A3ZI83)
3.A.1.3.17









Basic amino acid uptake transporter, BgtAB (BgtA is shared with NatFGH/BgtA; 3.A.1.3.18; Pernil et al., 2008)
Cyanobacteria
BgtAB of Anabaena sp. PCC7120
BgtA (C) (Q8YPM6)
BgtB (R-M) (Q8YSA2)
3.A.1.3.18









Acidic and neutral amino acid uptake transporter NatFGH/BgtA. BgtA is shared with BgtAB (3.A.1.3.17; Pernil et al., 2008)
Cyanobacteria
NatFGH-BgtA of Anabaena sp. PCC7120
BgtA (C) (Q8YPM6)
NatF (R) (Q8YPM9)
NatG (M) (Q8YPM8)
NatH (M) (Q8YPM7)
3.A.1.3.19









Acidic amino acid uptake porter, AatJMQP (Singh and Röhm, 2008)

Bacteria

AatJMQP of Pseudomonas putida
AatJ (R) Q88NY2
AatM (M) Q88NY3
AatQ (M) Q88NY4
AatP (C) Q88NY5
3.A.1.3.20









The putative lysine uptake system, LysXY

Bacteria

LysXY of Streptococcus pyogenes
LysX (R-M) (Q9A1H0)
LysY (C) (Q9A1H1)
3.A.1.3.21









Hydroxy L-proline uptake porter, HprABC (Johnson et al. 2008).

Proteobacteria

HprABC of Pseudomonas aeruginosa
HprA (C) (Q9I488)
HprB (M) (Q9I487)
HprC (R) (Q9I484)
3.A.1.3.22









Amino acid transporter, AatJMQP. Probably transports L-glutamic acid, D-glutamine acid, L-glutamine and N-acetyl L-glutamic acid (Johnson et al. 2008). Very similar to 3.A.1.3.19 of P. putida

Proteobacteria

AatJMQP of Pseudomonas aeruginosa
AatJ (R) (Q9I402)
AatM (M) (Q9I403)
AatQ (M) (Q9I404)
AatP (C) (Q9I405)
3.A.1.3.23









Amino acid transporter, PA5152-PA5155. Probably transports numerous amino acids including lysine, arginine, histidine, D-alanine and D-valine (Johnson et al. 2008). Regulated by ArgR.

Proteobacteria

PA5152-PA5144 of Pseudomonas aeruginosa
PA5152 (C) (Q9HU32)
PA5153 (R) (Q9HU31)
PA5154 (M) (Q9HU30)
PA5155 (M) (Q9HU29)
3.A.1.4:  The Hydrophobic Amino Acid Uptake Transporter (HAAT) Family
3.A.1.4.1









Leucine; leucine/isoleucine/valine porter (also transports phenylalanine and tyrosine; Koyanagi et al., 2004)
Proteobacteria
LivK (leucine-specific receptor)-LivJ (Leu/Ile/Val receptor)-LivHMGF of E. coli
LivJ (R)
LivK (R)
LivH (M)
LivM (M)
LivG (C)
LivF (C)
3.A.1.4.2









Leucine/proline/alanine/serine/glycine (and possibly histidine) porter
Cyanobacteria
NatA-E neutral amino acid porter of Synechocystis sp.PCC6803
NatA (C)
NatB (R)
NatC (M)
NatD (M)
NatE (C)
3.A.1.4.3









General L- (and D-)amino acid uptake porter (transports acidic, basic, polar, semipolar and hydrophobic amino acids). The amino and carboxyl groups do not need to be α since γ-aminobutyric acid (GABA) is a substrate. The system may function with additional binding proteins since L-alanine uptake is not dependent on BraC.
Proteobacteria
BraCDEF of Rhizobium leguminosarum
BraC (R)
BraD (M)
BraE (M)
BraF (C)
3.A.1.4.4









The high-affinity (<1 μM) urea porter
Cyanobacteria
UrtA-E urea porter of Anabaena sp. PCC7120
UrtA (R)
UrtB (M)
UrtC (M)
UrtD (C)
UrtE (C)
3.A.1.4.5









The high affinity urea/thiourea/hydroxyurea porter (Beckers et al., 2004)
Actinobacteria
UrtA-E of Corynebacterium glutamicum
UrtA (R) CAF19637
UrtB (M) CAF19636
UrtC (M) CAF19638
UrtD (C) CAF19639
UrtE (C) CAF19640
3.A.1.4.6









The neutral amino acid permease, N-1 (transports pro, phe, leu, gly, ala, ser, gln and his, but gln and his are not transported via NatB) (Picossi et al., 2005)
Cyanobacteria
NatA-E of Anabaena sp. strain PCC7120
NatA (C) BAB73003
NatB (R) BAB73533
NatC (M) BAB73004
NatD (M) BAB73241
NatE (C) BAB74611
3.A.1.4.7









The protocatechuate (3,4-dihydroxybenzoate) uptake porter, PcaMNVWX (Maclean et al., 2011)

δ-Proteobacteria

PcaMNVWX of Sinorhizobium (Ensifer) meliloti
PcaM (R) (Q92TN0)
PcaN (M) (Q92TN1)
PcaV (M) (Q92TN2) 
PcaW (C) (Q92TN3) 
PcaX (C) (Q92TN4) 
3.A.1.4.8









Branched chain amino acid uptake transporter. Transports alanine (Hoshino and Kose 1990).

Proteobacteria

BraC-G of Pseudomonas aeruginosa
BraG (C) (P21630)
BraE (C) (P21629)
BraE (M) (P21628)
BraD (M) (P21627)
BraC (R) (P21175)
3.A.1.5:  The Peptide/Opine/Nickel Uptake Transporter (PepT) Family
3.A.1.5.1









Oligopeptide porter (also takes up amino glycoside antibiotics such as kanamycin, streptomycin and neomycin as well as cell wall-derived peptides such as murein tripeptide). It transports substrate peptides of 2-5 amino acids with highest affinity for tripeptides. Also transports δ-aminolevulinic acid (ALA). [May be regulated by PTS Enzyme INtr-aspartokinase.] ATP-binding to OppDF may result in donation of peptide to OppBC and simultaneous release of OppA (Doeven et al., 2008).
Proteobacteria
OppABCDF of Salmonella typhimurium
OppA (R)
OppB (M)
OppC (M)
OppD (C)
OppF (C)
MppA (R) (in E. coli)
3.A.1.5.2









Dipeptide porter. Also transports δ-aminolevulinic acid (ALA) and heme (Létoffé et al., 2008).
Firmicutes
DppABCDE of Bacillus subtilis
DppA (C)
DppB (M)
DppC (M)
DppD (C)
DppE (R)
3.A.1.5.3









Nickel porter. Histidine 416 of NikA is essential for nickel uptake (Cavazza et al., 2011).

Proteobacteria

NikABCDE of E. coli
NikA (R)
NikB (M)
NikC (M)
NikD (C)
NikE (C)
3.A.1.5.4









Agrocinopine (an opine)/Agrocin 84 (an antibiotic) porter (Kim and Farrand, 1997)
Proteobacteria
AccABCDE of Agrobacterium tumefaciens
AccA (R)
AccB (C)
AccC (C)
AccD (M)
AccE (M)
3.A.1.5.5









Probable cationic peptide porter (may also take up peptide antibiotics and protamine; implicated in K+ homeostasis) [SapD can stimulate the K+ uptake activities of TrkH and TrkG (TC #2.A.38.1.1) in the presence of ATP] (Mason et al., 2006)
Bacteria
SapABCDF of Salmonella typhimurium
SapA (R)
SapB (M)
SapC (M)
SapD (C)
SapF (C)
3.A.1.5.6









The β-glucoside (cellobiose (β-1,4), cellotriose, cellotetraose, cellopentaose, laminaribiose (β-1,3), laminaritriose, sophorose) uptake porter, CbtABCDF
Archaea
The β-glucoside uptake porter of Pyrococcus furiosus, CbtABCDF
CbtA (R)
CbtB (M)
CbtC (M)
CbtD (C)
CbtF (C)
3.A.1.5.7









The α-galactoside (melibiose, raffinose) uptake porter, AgpABCDF
Bacteria
The α-galactoside uptake porter of Rhizobium meliloti
AgpA (R)
AgpB (M) (not identified)
AgpC (M) (not identified)
AgpD (C) (not identified)
AgpF (C) (not identified)
3.A.1.5.8









Maltose and maltooligosaccharide porter

Archaea

MalEFGK of Sulfolobus solfataricus
MalE (R)
MalF (M)
MalG (M)
MalK (C-C)
3.A.1.5.9









Cellobiose and cellooligosaccharide porter
Archaea
CbtABCDF of Sulfolobus solfataricus
CbtA (R)
CbtB (M)
CbtC (M)
CbtD (C)
CbtF (C)
3.A.1.5.10









Oligopeptide porter (transports peptides of 4-35) amino acyl residues; di- and tripeptides are not transported; hydrophobic basic peptides are preferred). OppA determines the specificity of the system (Doeven et al., 2004). A large cavity in OppA binds proline-rich peptides preferentially (Berntsson et al., 2009). Two crystal structures of OppA with different nonapeptides show binding in different registers (Berntsson et al., 2011).

Bacteria

OppABCDF of Lactococcus lactis
OppA (R) (Q9CEK0)
OppB (M) (P0A4N7)
OppC (M) (P0A4N9)
OppD (C) (Q07733)
OppF (C) (P0A2V4)
3.A.1.5.11









Glutathione porter (Suzuki et al., 2005)

Bacteria

YliABCD of E. coli
YliA (C-C) (P75796)
YliB (R) (P75797)
YliC (M) (P75798)
YliD (M) (P75799)
3.A.1.5.12









Probable rhamnose oligosaccharide porter. Induced by rhamnose (Conners et al., 2005).

Thermotogae

RtpEFGKL of Thermotoga maritima
RtpE (R) (TM1067) Q9X0F7
RtpF (M) (TM1066) Q9X0F6
RtpG (M) (TM1065) Q9X0F5
RtpK (C) (TM1064) Q9X0F4
RtpL (C) (TM1063) Q9X0F3
3.A.1.5.13









Probable xylan oligosaccharide porter (Conners et al., 2005). Induced by xylan and xylose. Regulated by xylose-responsive regulator XylR (Kazanov et al. 2012).

Thermotogae

XloEFGKL of Thermotoga maritima
XloE (R) (TM0071) Q9WXS6
XloF (M) (TM0072) Q9WXS7
XloG (M) (TM0073) Q9WXS8
XloK (C) (TM0074) Q9WXS9
XloL (C) (TM0075) Q9WXT5
3.A.1.5.14









Probable cellobiose porter. Induced by barley, glucomannan (Conners et al., 2005)

Thermotogae

CelEFGKL of Thermotoga maritima
CelE (R) (TM1223) Q9X0V0
CelF (M) (TM1222) Q9X0U9
CelG (M) (TM1221) Q9X0U8
CelK (C) (TM1220) Q9X0U7
CelL (C) (TM1219) Q9X0U6
3.A.1.5.15









Probable mannose/mannoside porter. Induced by beta-mannan (Conners et al., 2005). Regulated by mannose-responsive regulator manR (Kazanov et al., 2012).

Thermotogae

MtpEFGKL of Thermotoga maritima
MtpE (R) (TM1746) Q9X268
MtpF (M) (TM1747) Q9X269
MtpG (M) (TM1748) Q9X270
MtpK (C) (TM1749) Q9X271
MtpL (C) (TM1750) Q9X272
3.A.1.5.16









β-glucoside porter (Conners et al., 2005). Binds cellobiose, laminaribiose (Nanavati et al. 2006). Regulated by cellobiose-responsive repressor BglR (Kazanov et al. 2012).

Thermotogae

BglpEFGKL of Thermotoga maritima
BglE (R) (TM0031) Q9WXN8
BglF (M) (TM0030) Q9WXN7
BglG (M) (TM0029) Q9WXN6
BglK (C) (TM0028) Q9WXN5
BglL (C) (TM0027) Q9WXN4
3.A.1.5.17









The proline betaine uptake porter (Alloing et al., 2006)

Proteobacteria
PrbABCD of Sinorhizobium meliloti
PrbA (R) (Q92NF1)
PrbB (M) (Q92NF0)
PrbC (M) (Q92NE9)
PrbD (C-C) (Q92NE8)
3.A.1.5.18









The oligopeptide transporter OppA1-5, B1, C1, DF (functions with five binding proteins of differing induction properties and peptide specificities; OppA1-3 are chromosomally encoded; OppA4 and 5 are plasmid encoded.) (Medrano et al., 2007)
Bacteria
OppA1-5,B1,C1,D,F of Borrelia burgdorferi
OppA1 (R): O51307
OppA2 (R): O54584
OppA3 (R): O51308
OppA4 (R): O31315
OppA5 (R): O50927
OppB1 (M): O31307
OppC1 (M): O51310
OppD (C): O31309
OppF (C): O31310
3.A.1.5.19









The major oligopeptide uptake porter, Opp-3 (of four paralogues, this is the only one that mediates nitrogen nutrition (Hiron et al., 2007).
Bacteria
Opp-3 of Staphylococcus aureus
OppB (M) = (Q2FZR7)
OppC (M) = (Q2FZR6)
OppD (C) = (Q2FZR5)
OppF (C) = (Q2FZR4)
OppA (R) = (Q2FZR3)
3.A.1.5.20









5-6 amino acyl oligopeptide transporter AppA-F (Koide and Hoch, 1994).
Bacteria
AppABCDF of Bacillus subtilis
AppA(R) (P42061)
AppB(M) (P42062)
AppC(M) (P42063)
AppD(C) (P42064)
AppF(C) (P42065)
3.A.1.5.21









The Microcin C uptake porter, YejABEF (other substrate unknown) (Novikova et al., 2007)

Bacteria

YejABEF of E. coli:
YejA (R) (P33913)
YejB (M) (P0AFU1)
YejE (M) (P33915)
YejF (C-C) (P33916)
3.A.1.5.22









The peptide transporter OppA,B,C,D,F (influences biofilm formation; Lee et al., 2004). Similar to 3.A.1.5.1, OppA is similar to the Vibrio furnissii OppA that provides several functions: hemolysis, antibiotic resistance, and virulence (Wu et al., 2007).
Bacteria
OppABCDF of Vibrio fluvialis:
OppA (R) (Q5V9S2)
OppB (M) (Q5V9S1)
OppC (M) (Q5V9S0)
OppD (C) (Q5V9R9)
OppF (C) (Q5V9R8)
3.A.1.5.23









The Ethylene diamine tetraacetate (EDTA) uptake porter, EppABCD (Zhang et al., 2007).

Bacteria

EppABCD of EDTA-degrading bacterium BNC1:
EppA (R) (Q9F9T7)
EppB (M) (Q9F9T6)
EppC (M) (Q9F9T5)
EppD (C-C) (Q9F9T4)
3.A.1.5.24









The antimicrobial peptide (protamine, melittin, polymyxin B, human defensin (HBD)-1 and HBD-2 exporter, YejABEF (Eswarappa et al., 2008). Prefers N-formyl methionine peptides, such as Microcin C (of prokaryotic origin) to non formylated peptides (of eukaryotic origin) (Novikova et al., 2007).

Proteobacteria
YejABEF of Salmonella enterica
YejA (R) (Q8ZNK0)
YejB (M) (Q7CQ74)
YejE (M) (Q8ZNJ9)
YejF (C-C) (Q8ZNJ8)
3.A.1.5.25









The ABC peptide/signalling peptide transporter. OptA binds peptides of 3-6 aas; OptS binds dipeptides. OptB,C,D are most similar to 3.A.1.5.19.

Gram-positive bacteria

The OptASBCDF transport system of Lactococcus lactis
OptS (R) (Q64K09)
OptA (R) (Q9CIL2)
OptB (M) (Q9CILI)
OptC (M) (Q9CIL0)
OptD (C) (Q9CIK9)
OptF (C) (Q9CIK8)
3.A.1.5.26









The glutamine transporter, OppA (Dasgupta et al., 2010). OppA binds glutathione and the nanopeptide, bradykinin. Also regulates cytokine release, apoptosis and the innate immune response of macrophages infected with M. tuberculosis (Dasgupta et al., 2010).

Bacteria

Peptide transporter of Mycobacterium tuberculosis
OppA (R) (P66771)
OppD (C) (P63395)
OppC (M) (P66964)
OppB (M) (P66966)
3.A.1.5.27









The glutathione uptake porter, DppBCDF with the glutathione binding protein, DppA (GbpA; HbpA). Takes up reduced (GSH) and oxidized (GSSG) but not bulky glutathione S conjugates or glutathione derivatives with C-terminal modifications (Vergauwen et al., 2010).

Bacteria

DppABCDF of Haemophilus influenzae
DppA (R) (P33950)
DppB (M) (P45096)
DppC (M) (P51000)
DppD (C) (P45095)
DppF (C) (P45094)
3.A.1.5.28









The Nickel (Ni2+) uptake porter, NikZYXWV (Howlett et al., 2012).

Bacteria

NikZYXWV of Campylobacter jejuni 
NikZ (R) (Q0P844)
NikY (M) (Q0P845)
NikX (M) (Q0P846)
NikW (C) (Q0P847)
NikV (C) (Q0P848) 
3.A.1.5.29









Probable xylan oligosaccharide porter (Conners et al. 2005). Induced by cylan and xylose. Regulated by xylose-responsive regulator XylR (Kazanov et al. 2012).

Thermotogae

XtpELKGF of Thermotoga maritima
XtpE (R) (TM0056) (Q9WXR2)
XtpL (C) (TM0057) (Q9WXR3)
XtpK (C) (TM0058) (Q9WXR4)
XtpG (M) (TM0059) (Q9WXR5)
XtpF (M) (TM0060) (Q9WXR6)
3.A.1.5.30









Putative fucose-glucose oligosaccharide porter. Binds xyloglucan hepta-, octa-, nonasaccharides with beta-1,4- tetraglucosyl backbones (Conners et al., 2005)

Thermotogae

GloEFGKL of Thermotoga maritima
GloE (R) (TM0300) (Q9WYD6)
GloF (M) (TM0301) (Q9WYD7)
GloG (M) (TM0302) (Q9WYD8)
GloK (C) (TM0303) (Q9WYD9)
GloL (C) (TM0304) (Q9WYE0)  
3.A.1.5.31









Predicted galactoside porter. Induced by lactose (Conners et al., 2005)

Thermotogae

LtpE (R) (TM1199) Q9X0S6 LtpF (M) (TM1198) Q9X0S5 LtpG (M) (TM1197) Q9X0S4 LtpK (C) (TM1196) Q9X0S3 LtpL (C) (TM1194) Q9S5X6
3.A.1.6:  The Sulfate/Tungstate Uptake Transporter (SulT) Family
3.A.1.6.1









Sulfate/thiosulfate porter
Proteobacteria
Sbp (sulfate receptor)-CysP (thiosulfate receptor)-CysTWA of E. coli
Sbp (R)
CysP (R)
CysT (M)
CysW (M)
CysA (C)
3.A.1.6.2









Tungstate porter. (TupA, the receptor, exhibits an extremely high affinity for tungstate (Kd <1 nM) and discriminates between tungstate and molybdate (Andreesen and Makdessi, 2007))
Firmicutes
TupABC of Eubacterium acidaminophilum
TupA (R)
TupB (M)
TupC (C)
3.A.1.6.3









Sulfate porter
Actinobacteria
CysAWT SubI-sulfate porter of Mycobacterium tuberculosis
CysA (C)
CysW (M)
CysT (M)
SubI (R)
3.A.1.6.4









Vanadate porter (Pratte and Thiel, 2006) (most similar to TupABC (3.A.1.6.2))
Cyanobacteria
VupABC of Anabaena variabilis ATCC29413
VupA (R) (ABA23645)
VupB (M) (ABA23644)
VupC (C) (ABA23643)
3.A.1.6.5









Tungsten (KM=20pM)/molybdate (KM=10nM) porter (Bevers et al., 2006)
Euryarchaeota
WtpABC of Pyrococcus furiosus
WtpA (R) (Q8U4K5)
WtpB (M) (Q8U4K4)
WtpC (C) (Q8U4K3)
3.A.1.6.6









The Molybdate/Tungstate Transporter, ModA-C (Zhang and Gladyshev, 2008).

Archaeon

ModABC of Pyrobaculum calidifontis
ModA (R) (A3MW02)
ModB (M) (A3MW01)
ModC (C) (A3MW00)
3.A.1.6.7









The chloroplast sulfate transporter, SulP/SulP2/Sabc/Sbp (Melis & Chen et al., 2005).

Algae

Chloroplast sulfate uptake permease of Chlamydomonas reinhardtii
SulP (M) (Q8RVC7)
SulP2 (M) (Q6QJE2)
Sabc (C) (Q6QJE1)
Sbp (R) (Q6QJE0)
3.A.1.6.8









Molybdate/tungstate transport system, ModABC (WtpABC) (ModA binds to ModBC with high affinity (0.11%u03BCM) and dissociates slowly; the complex is destabilized by nucleotide and substrate binding (Vigonsky et al. 2013).

Archaea

ModABC of Archeoglobus fulgidus
ModB (M; 12 TMSs; type I fold) (O30143)
ModC (C) (O30144)
ModA (R) (O30142)
3.A.1.7:  The Phosphate Uptake Transporter (PhoT) Family
3.A.1.7.1









Phosphate porter
Proteobacteria
PhoS (phosphate receptor)-PstABC of E. coli
PhoS (R)
PstA (M)
PstC (M)
PstB (C)
3.A.1.7.2









Phosphate transporter, PstSCAB (Gebhard and Cook, 2007).
Actinobacteria
PstSCAB of Mycobacterium smegmatis
PstS (R) (Q7WTY8)
PstC (M) (Q7WTY7)
PstA (M) (Q7WTY6)
PstB (C) (P0C560)
3.A.1.7.3









High-affinity phosphate-specific permease, PstAB/PhoS. The 3-d structure of PhoS = (PBP) = PfluDING) has been solved at high resolution by x-ray crystallography (Ahn et al. 2007) with phosphate bound (4F1U and 4F1V; 0.95Å resolution) and with arsenate bound (4F18 and 4F19; 0.88Å resolution) (Elias et al. 2012). Phosphate binds with 500-fold higher affinity than arsenate due to a dense and rigid network of ion-dipole interactions (Elias et al. 2012). The PBP from Halomonas sp. GFAJ-1 has a phosphate affinity 5000-fold higher than that of arsenate (Elias et al. 2012).

Bacteria

PstAB/PhoS of Pseudomonas fluorescens
PstA (C) (C3KCB5)
PstB (M) (C3KCB6)
PstC (PBP) (R) (D0VWY2) 
3.A.1.8:  The Molybdate Uptake Transporter (MolT) Family
3.A.1.8.1









Molybdate porter
Proteobacteria
ModABC of E. coli
ModA (R)
ModB (M)
ModC (C)
3.A.1.8.2









The molybdate/tungstate ABC transporter, ModABC. The trans-inhibited 3-d structure of ModABC, is available (3D31.A and 3D31.B)(Gerber et al., 2008)

Archaea

ModABC of Methanosarcina acetivorans
ModA (Q8TTV0)
ModB (M) (Q8TJ86)
ModC (C) (Q8TTV2)
3.A.1.9:  The Phosphonate Uptake Transporter (PhnT) Family
3.A.1.9.1









Phosphonate/organophosphate ester porter (broad specificity). Reviewed by Hinz & Tampé (2012).

Proteobacteria

PhnCDE of E. coli
PhnC (C)
PhnD (R)
PhnE (M)
3.A.1.9.2









Phosphonate/phosphate porter, PhnDCE (Gebhard and Cook, 2007)
Bacteria
PhnDCE of Mycobacterium smegmatis
PhnC (C) (A0QQ70)
PhnD (R) (A0QQ71)
PhnE (M) (A0QQ68)
3.A.1.10:  The Ferric Iron Uptake Transporter (FeT) Family
3.A.1.10.1









Ferric iron (Fe3+) porter
Proteobacteria
SfuABC of Serratia marcescens
SfuA (R)
SfuB (M)
SfuC (C)
3.A.1.10.2









Ferric iron (Fe3+) porter
Cyanobacteria
Fut A1A2BC of SynechocystisPCC6803
FutA1 (R)
FutA2 (R)
FutB (M)
FutC (C)
3.A.1.10.3









Ferric iron (Fe3+) porter (selective for trivalent cations, Fe3+, Ga3+ and Al3+) (Anderson et al., 2004)
Proteobacteria
FbpABC (HitABC) of Haemophilus influenzae
FbpA (R) (AAC21773)
FbpB (M) (AAC21774)
FbpC (C) (AAC21775)
3.A.1.10.4









The Fe-hydroxamate-type siderophore uptake porter (transports Fe+3 bound to ferrioxamine, ferrichrome or pyoverdine siderophores) (Vajrala et al., 2010).

Bacteria

NitABC of Nitrosomonas europaea
NitA (R) (Q82VN7)
NitB (M) (Q82VN6)
NitC (C) (Q82VN5)
3.A.1.11:  The Polyamine/Opine/Phosphonate Uptake Transporter (POPT) Family
3.A.1.11.1









Polyamine (putrescine/spermidine) porter
Proteobacteria
PotABCD of E. coli
PotA (C)
PotB (M)
PotC (M)
PotD (R)
3.A.1.11.2









Putrescine porter
Proteobacteria
PotGHIF of E. coli
PotG (C)
PotH (M)
PotI (M)
PotF (R)
3.A.1.11.3









Mannopine porter
Proteobacteria
MotABCD of Agrobacterium tumefaciens plasmid pTi15955
MotA (R)
MotB (C)
MotC (M)
MotD (M)
3.A.1.11.4









Chrysopine porter
Proteobacteria
ChtGHIJK of Agrobacterium tumefaciens
ChtG (C)
ChtH (R)
ChtI (R)
ChtJ (M)
ChtK (M)
3.A.1.11.5









2-aminoethyl phosphonate porter
Proteobacteria
PhnSTUV of Salmonella typhimurium
PhnS (R)
PhnT (C)
PhnU (M)
PhnV (M)
3.A.1.11.6









The γ-aminobutyrate (GABA) uptake system, GtsABCD (White et al., 2009).

Bacteria

GtsABCD of Rhizobium leguminosarum
GtsA (R) (Q1M7Q4)
GtsB (M) (Q1M7Q3)
GtsC (M) (Q1M7Q2)
GtsD (C) (Q1M7Q1)
3.A.1.12:  The Quaternary Amine Uptake Transporter (QAT) Family (Similar to 3.A.1.16 and 3.A.1.17)
3.A.1.12.1









Glycine betaine/proline porter, ProU or ProVWX (also transports proline betaine, carnitine, dimethyl proline, homobetaine, γ-butyrobetaine and choline with low affinity).  Contributes to the regulation of cell volume is response to osmolarity.  A reconsituted system shows osmotic strength-gating (Gul and Poolman 2012).

Proteobacteria

ProVWX of E. coli
ProW (M)
ProX (R)
ProV (C)
3.A.1.12.2









Glycine betaine porter (also transports dimethylsulfonioacetate and dimethylsulfoniopropionate)
Firmicutes
OpuAA, AB, AC of Bacillus subtilis
OpuAA (C)
OpuAB (M)
OpuAC (R)
3.A.1.12.3









Choline porter
Firmicutes
OpuBA, BB, BC, BD of Bacillus subtilis
OpuBA (C)
OpuBB (M)
OpuBC (R)
OpuBD (M)
3.A.1.12.4









Uptake system for choline, L-carnitine, D-carnitine, glycine betaine, proline betaine, crotonobetaine, γ-butyrobetaine, dimethylsulfonioacetate, dimethylsulfoniopropionate, ectoine and choline-O-sulfate
Firmicutes
OpuCA, CB, CC, CD of Bacillus subtilis
OpuCA (C)
OpuCB (M)
OpuCC (R)
OpuCD (M)
3.A.1.12.5









Uptake system for glycine-betaine (high affinity) and proline (low affinity) (OpuAA-OpuABC) or BusAA-ABC of Lactococcus lactis). BusAA, the ATPase subunit, has a C-terminal tandem cystathionine β-synthase (CBS) domain which is the cytoplasmic K+ sensor for osmotic stress (osmotic strength)while the BusABC subunit has the membrane and receptor domains fused to each other (Biemans-Oldehinkel et al., 2006; Mahmood et al., 2006; Gul et al. 2012). An N-terminal amphipathic α-helix of OpuA is necessary for high activity but is not critical for biogenesis or the ionic regulation of transport (Gul et al., 2012).

Firmicutes

BusAA-AB of Lactococcus lactis
BusAA (C-CBS)
BusAB (M-R)
3.A.1.12.6









Uptake system for hisitidine, proline, proline-betaine and glycine-betaine
Proteobacteria
HutXWV of Sinorhizobium meliloti
HutX (R)
HutW (M)
HutV (C)
3.A.1.12.7









High affinity (3 μM) choline-specific uptake system (Dupont et al., 2004)
Proteobacteria
ChoXWV of Sinorhizobium meliloti
ChoX (R) (AAM00244)
ChoW (M) (AAM00245)
ChoV (C) (AAM00246)
3.A.1.12.8









A proline/glycine betaine uptake system. Also reported to be a bile exclusion system that exports oxgall and other bile compounds, BilEA/EB or OpuBA/BB (required for normal virulence) (R.D. Sleator et al., 2005).
Bacteria
OpuBA/BB or BilEA/EB of Listeria monocytogenes
OpuBA (C) (Q93A35)
OpuBB (M-R) (Q93A34)
3.A.1.12.9









The salt-induced glycine betaine OtaABC transporter (Schmidt et al., 2007)
Archaea
OtaABC of Methanosarcina mazei Go1
OtaA (C) Q8U4S5
OtaB (M) Q8U4S4
OtaC (R) Q8U4S3
3.A.1.12.10









The OpuC transporter selective for glycine betaine > choline, acetylcholine, carnitine and proline betaine (contains tandem cystathionine-β-synthase (CBS) domains in the ABC component of OpuC that are required for osmoregulatory function (Chen and Beattie, 2007)).
Proteobacteria
OpuCA, CB, CC of Pseudomonas syringae
OpuCC (R) (Q87WH3)
OpuCB (M) (Q87WH4)
OpuCA (C) (Q87WH5)
3.A.1.12.11









The glycine betaine uptake porter, GbpABCD (Saum et al., 2009).

Archaea

GbpABCD of Methanosarcina mazei
GbpA (R) (Q8Q040)
GbpB (M) (Q8Q043)
GbpC (M) (Q9Q042)
GbpD (C) (Q8Q041)
3.A.1.12.12









The CbcWV/CbcX (choline)/CaiX (carnitine)/BetX (betaine) transporter with 3 binding receptors for distinct quaternary ammonium compounds. Only the ligand-bound receptor binds to the transporter with high affinity (Chen et al., 2010; Thomas et al., 2010).

Bacteria

CbcWV/CbcX/CaiX/BetX of Pseudomonas aeruginosa
CbcW (M) (Q9HTI7)
CbcV (C) (Q9HTI8)
CbcX (R) (Q9HTI6)
CaiX (R) (Q9HTH6)
BetX (R) (Q9HZ04)
3.A.1.12.13









High affinity (2mμM) choline uptake porter. The choline binding receptor exhibits a venus fly trap mechanism of substrate binding. (ChoX binds acetyl choline and betaine with low affinity (80μM and 470μM, respectively) (Aktas et al., 2011) (most similar to 3.A.1.12.7)

Bacteria

ChoVWX of Agrobacterium tumefaciens 
ChoX (R) (Q7CXG0)
ChoW (M) (Q7CXG1)
ChoV (C) (A9CI32)
3.A.1.12.14









OsmU (OsmVWXY) transporter for glycine betaine and choline-O-sulfate uptake. Induced by osmotic stress (0.3M NaCl) (Frossard et al., 2012).

Proteobacteria

OsmU or OsmVWXY of Salmonella enterica 
OsmV (STM1491) (C) (Q8ZPK4)
OsmW (STM1492) (M) (Q8ZPK3)
OsmX (STM1493) (R) (Q8ZPK2)
OsmY (STM1494) (M) (Q8ZPK1) 
3.A.1.13:  The Vitamin B12 Uptake Transporter (B12T) Family (Similar to 3.A.1.14)
3.A.1.13.1









Vitamin B12 porter. The 3-D structure of BtuCDF has been solved to 2.6Å (Hvorup et al., 2007). The conformational transition pathways of BtuCD has been revealed by targeted molecular dynamics simulation (Weng et al., 2012). Asymmetric states of BtuCD are not discriminated by its cognate substrate binding protein BtuF (Korkhov et al., 2012).

Proteobacteria

BtuCDF of E. coli
BtuC (M)
BtuD (C)
BtuF (R)
3.A.1.14:  The Iron Chelate Uptake Transporter (FeCT) Family (Similar to 3.A.1.13 and 3.A.1.15)
3.A.1.14.1









Iron (Fe3+) or ferric-dicitrate porter (Braun and Herrmann, 2007)
Proteobacteria
FecBCDE of E. coli
FecB (R)
FecC (M)
FecD (M)
FecE (C)
3.A.1.14.2









Iron (Fe3+)-enterobactin porter

Proteobacteria

FepBCDG of E. coli
FepB (R) (C8U2V6)
FepC (C) (P23878)
FepD (M) (P23876)
FepG (M) (P23877)
3.A.1.14.3









Iron (Fe3+)-hydroxamate (ferrichrome, coprogen, aerobactin, ferrioxamine B, schizakinen, rhodotorulic acid) porter, albomycin porter
Proteobacteria
FhuBCD of E. coli
FhuB (M-M; 20 TMSs; 10+10)
FhuC (C)
FhuD (R)
3.A.1.14.4









Iron-chrysobactine porter
Proteobacteria
CbrABCD of Erwinia chrysanthemi
CbrA (R)
CbrB (M)
CbrC (M)
CbrD (C)
3.A.1.14.5









Heme (hemin) uptake porter. The receptor, HmuT, binds two parallel stacked heme molecules, and two are transported per reaction cycle (Mattle et al., 2010).

Proteobacteria

HmuTUV of Yersinia pestis
HmuT (R) (Q56991)
HmuU (M) (Q56992)
HmuV (C) (Q56993)
3.A.1.14.6









The iron-vibriobactin/enterobactin uptake porter
Proteobacteria
ViuPDGC of Vibrio cholerae
ViuP (R)
ViuD (M)
ViuG (M)
ViuC (C)
3.A.1.14.7









Iron (Fe3+)-hydroxamate porter (transports Fe3+-ferrichrome and Fe3+-ferrioxamine B with FhuD1, and these compounds plus aerobactin and coprogen with FhuD2).
Firmicutes
FhuBCD1D2 of Staphylococcus aureus
FhuB (M)
FhuC (C)
FhuD1 (R)
FhuD2 (R)
3.A.1.14.8









The iron-vibrioferrin uptake porter (Tanabe et al., 2003)
Proteobacteria
PvuBCDE of Vibrio parahaemolyticus
PvuB (R) (BAC16540)
PvuC (M) (BAC16541)
PvuD (M) (BAC16542)
PvuE (C) (BAC16543)
3.A.1.14.9









The Corrinoid porter, BtuCDE (Woodson et al., 2005)
Archaea
BtuCDE of Halobacterium sp. strain NRC-1
BtuC (M) (AAG19698)
BtuD (C) (NP_444218)
BtuE (R) (AAG19697)
3.A.1.14.10









The heme porter, Shp/SiaABC (HtsABC). Shp is a cell surface heme binding protein that transfers the heme directly to HstA (Nygaard et al., 2006). The crystal structure of the heme binding domain of Shp has been solved (Aranda et al., 2007). HtsABC is required for the uptake of staphyloferrin A (Beasley et al. 2009). The Shr cell surface heme receptor may feed iron-heme to Shp in preparation for uptake (Ouattara et al., 2010). 

Bacteria

Shp/HtsABC of Streptococcus pyogenes
Shp (R1) (291 aas; Q1J548)
HtsA (R2) (294 aas; Q99YA2)
HtsB (M) (340 aas; Q99YA3)
HtsC (C) (278 aas; Q99YA4)
3.A.1.14.11









The molybdate/tungstate ABC transporter, MolABC.  For MolC; HI1470(C)/MolB; HI1471(M), the 3D structure is known at 2.4 Å resolution; Pinkett et al., 2007).  MolA binds to MolBC with low affinity (50 - 100 %u03BCM), forming a transient complex that is stabilitzed by ligand binding (Vigonsky et al. 2013).

Bacteria

MolABC of Haemophilus influenzae
MolC; HI1470 (C) (Q57399)
MolB; HI1471 (M; 10 TMSs; type II fold) (Q57130)
MolA; HI1472 (R) (E3GUW2)
3.A.1.14.12









Desferrioxamine B uptake porter, DesABC (Barona-Gomez et al., 2006)
Bacteria
DesABC of Streptomyces coelicolor
DesA (R) (CAB76300)
DesB (M-M; 18 TMSs; 9+9 TMSs) (CAB76299)
DesC (C) (CAB76301)
3.A.1.14.13









Coelichelin uptake porter, CchCDEF (Barona-Gomez et al., 2006)
Bacteria
CchCDEF of Streptomyces coelicolor
CchC (M) (CAB53327)
CchD (M) (CAB53326)
CchE (C) (CAB53325)
CchF (R) (CAB53324)
3.A.1.14.14









The Fe3+ uptake porter; SiuABDG (Montañez et al., 2005)

Bacteria

SiuABDG (FtsABCD) of Streptococcus pyogenes
SiuA; FtsA (C) (Q9A197)
SiuD; FtsB (R) (Q9A199)
SiuB; FtsC (M) (Q9A198)
SiuG; FtsD (M) (Q06A41) 
3.A.1.14.15









Uptake transporter for the catecholic trilactone (2, 3-dihydroxybenzoate-glycine-threonine)3 siderophore bacillibactin (for ferric iron scavenging), FeuABC (Gaballa and Helmann, 2007; Miethke et al., 2006).

Bacteria

FeuABC of Bacillus subtilis
FeuA (R) (P40409)
FeuB (M) (P40410)
FeuC (M) (P40411)
3.A.1.14.16









The heme-specific uptake porter, HemTUV (Létoffé et al., 2008).

Bacteria

HemTUV of Serratia proteamaculans
HemT (R) - (A8GDS8)
HemU (M) - (A8GDS7)
HemV (C) - (A8GDS6)
3.A.1.14.17









Heme acquisition ABC uptake transporter, IsdDEF (Liu et al., 2008)
Firmicutes
IsdDEF of Staphylococcus aureus
IsdD (?) (358aas, 2TMSs) (Q5HGV2)
IsdE (R) (295aas, 1TMS) (Q7A652)
IsdF (M) (273aas; 8TMSs) (Q7A651)
3.A.1.14.18









The heme uptake porter, ShuTUV (Burkhard and Wilks, 2008). Transports a single heme per reaction cycle (Mattle et al., 2010). (3-d structure of ShuT is known (2RG7).

Bacteria

ShuTUV of Shigella dysenteriae
ShuT(R) (Q32AX9)
ShuU(M) (Q32AY2)
ShuV(C) (Q32AY3)
3.A.1.14.19









Heme uptake porter, HugBCD (Villarreal et al., 2008); also called HmuTUV.

Bacteria

HugBCD of Plesiomonas shigelloides
HugB (R) (Q93SS3)
HugC (M) (Q93SS2)
HugD (C) (Q93SS1)
3.A.1.14.20









Heme-iron (hemin) utilization transporter BhuTUV ( Brickman et al., 2006; Vanderpool and Armstrong, 2004).

Gram-negative bacteria

BhuTUV of Bordetella pertussis
BhuT (R) (Q7VSQ6)
BhuU (M) (Q7W024)
BhuV (C) (Q7W025)
3.A.1.14.21









The heme uptake porter, PhuTUV (transports one heme per reaction cycle) (Mattle et al., 2010).

Bacteria

PhuTUV of Pseudomonas aeruginosa
PhuT (R) (Q9HV90)
PhuU (M) (O68878)
PhuV (C) (O68877)
3.A.1.15:  The Manganese/Zinc/Iron Chelate Uptake Transporter (MZT) Family (Similar to 3.A.1.12, 3.A.1.14 and 3.A.1.16)
3.A.1.15.1









Manganese (Mn2+) porter
Cyanobacteria
MntABC of Synechocystis 6803
MntA (C)
MntB (M)
MntC (R)
3.A.1.15.2









Manganese (Mn2+) and zinc (Zn2+) porter
Firmicutes
ScaABC of Streptococcus gordonii
ScaA (R)
ScaB (M)
ScaC (C)
3.A.1.15.3









Zinc (Zn2+) porter
Firmicutes
AdcABC of Streptococcus pneumoniae
AdcA (R)
AdcB (M)
AdcC (C)
3.A.1.15.4









Iron and manganese porter
Proteobacteria
YfeABCD of Yersinia pestis
YfeA (R)
YfeB (C)
YfeC (M)
YfeD (M)
3.A.1.15.5









Zinc (Zn2+) porter (required for Zn2+ homeostasis and virulence of Salmonella enterica; Ammendola et al., 2007).
Proteobacteria
ZnuABC (YebLMI) of E. coli
ZnuA (R)
ZnuC (C)
ZnuB (M)
3.A.1.15.6









Iron (Fe2+)/Zinc (Zn2+)/Copper (Cu2+) porter
Firmicutes
MtsABC of Streptococcus pyogenes
MtsA (R)
MtsB (C)
MtsC (M)
3.A.1.15.7









Manganese (Mn2+) (Km=0.1 μM) and iron (Fe2+) (5 μM) porter (inhibited by Cd2+ > Co2+ > Ni2+, Cu2+) (most similar to YfeABCD of Yersinia pestis (TC #3.A.1.15.4)). Important for virulence in Salmonella (Karlinsey et al., 2010).

Proteobacteria

SitABCD of Salmonella typhimurium
SitA (R)
SitB (C)
SitC (M)
SitD (M)
3.A.1.15.8









Manganese (Mn2+), zinc (Zn2+) and possibly iron (Fe2+) porter (Hazlett et al., 2003)
Spirochaetes
TroABCD of Treponema pallidum
TroA (R) P96116
TroB (C) P96117
TroC (M) P96118
TroC (M) P96119
3.A.1.15.9









Manganese (Mn2+) and Iron (Fe2+) porter, SitABCD (Davies and Walker, 2007)
Bacteria
Sit ABCD of Sinorhizobium meliloti
SitA (R) - (Q92LL5)
SitB (M) - (Q92LL4)
SitC (C) - (Q92LL3)
SitD (M) - (Q92LL2)
3.A.1.15.10









The Mn2+/Zn2+ transporter MntABC (KB of Mn2+ and Zn2+ is 0.1μM which bind with equal affinity to the same site (Lim et al., 2008)
Bacteria
MntABC of Neisseria meningitidis:
MntA (C) (A1IQK5)
MntB (M) (A1IQK4)
MntC (R) (Q5FA63)
3.A.1.15.11









The zinc uptake porter, YcdHI-YceA (Gaballa et al., 2002).
Firmicutes
YcdHI-YceA of Bacillus subtilis
AdcA (YcdH) (R) (O34966)
AdcC (YcdI) (C) (O34946)
AdcB (YceA) (M) (O34610)
3.A.1.16:  The Nitrate/Nitrite/Cyanate Uptake Transporter (NitT) Family (Similar to 3.A.1.12 and 3.A.1.17)
3.A.1.16.1









Nitrate/nitrite porter
Cyanobacteria
NrtABCD of Synechococcus sp. (PCC 7942)
NrtA (R)
NrtB (M)
NrtC (C)
NrtD (C)
3.A.1.16.2









Bispecific cyanate/nitrite transporter (functions in both cyanate and nitrite assimilation; Maeda and Omata, 2009).
Cyanobacteria
CynABD of Synechococcus PCC7942
CynA (R)
CynB (M)
CynD (C)
3.A.1.16.3









Bicarbonate porter (activated by low [CO2] mediated by CmpR; (Nishimura et al., 2008))
Cyanobacteria
CmpABCD of Synechococcus sp.
CmpA (R)
CmpB (M)
CmpC (C)
CmpD (C)
3.A.1.16.4









Nitrate uptake system, NrtABCD (Frías et al., 1997)

Cyanobacteria

NrtABCD of Anabaena (Nostoc) sp. PCC 7120
NrtA (R) (Q44292)
NrtB (M) (Q8YRV7)
NrtC (C-R) (Q8YRV8)
NrtD (C) (Q8YZ25)
3.A.1.17:  The Taurine Uptake Transporter (TauT) Family (Similar to 3.A.1.12 and 3.A.1.16)
3.A.1.17.1









Taurine (2-aminoethane sulfonate) porter
Proteobacteria
TauABC of E. coli
TauA (R)
TauB (C)
TauC (M)
3.A.1.17.2









Aromatic sulfonate porter
Proteobacteria
SsuABC of Pseudomonas putida
SsuA (R)
SsuB (C)
SsuC (M)
3.A.1.17.3









Putative hydroxymethylpyrimidine transport system, ThiXYZ (Rodionov et al., 2002). Regulated by TPP (thiamin) riboswitch. Potentially takes up a pyrimidine moiety of thiamin.

Bacteria

ThiXYZ of Haemophilus influenzae
ThiZ (C) (P44656)
ThiX (M) (Q57306)
ThiY (R) (P44658)
3.A.1.17.4









The taurine uptake system, TauABC (Krejcík et al., 2008).

Proteobacteria

TauABC of Neptuniibacter caesariensis
TauA (R) (Q2BM68)
TauB (C) (Q2BM69)
TauC (M) (Q2BM70)
3.A.1.17.5









The phthalate uptake system, OphFGH (Chang et al. 2009).

Bacteria

OphFGH of Burkholderia capacia
OphF (R) (C0LZR7)
OphG (M) (C0LZR8)
OphH (C) (C0LZR9)
3.A.1.17.6









Putative hydroxymethylpyrimidine transport system, ThiXYZ (Rodionov et al., 2002). Regulated by TPP (thiamin) riboswitch. Potentially takes up a pyrimidine moiety of thiamin. ThiY is homologous to the yeast THI5 HMP-P synthase (P43534) (Bale et al., 2010).

Actinobacteria, Proteobacteria

ThiXYZ of Pasteurella multocida
ThiX (M) (Q9CLG9)
ThiY (R) (Q9CLH1)
ThiZ (C) (Q9CLG8)
3.A.1.17.7









Putative riboflavin transport system, RibXY. Regulated by FMN riboswitch (Vitreschak et al. 2002)

Chloroflexi

RibXY of Roseiflexus castenholziiRibX (M) (A7NLS3)RibY (R) (A7NLS2)
3.A.1.17.8









Putative thiamine transport system, ThiXYZ (Rodionov et al., 2002). Regulated by TPP (thiamin) riboswitch.

Chloroflexi

ThiXYZ of Roseiflexus castenholziThiX (M) (A7NH43)ThiY (R) (A7NH44)ThiZ (C) (A7NH45)
3.A.1.18:  The Cobalt Uptake Transporter (CoT) Family
3.A.1.18.1









Cobalt (Co2+) porter (Rodionov et al., 2006).  CbiMN is a bipartite S-subunit with 8 TMSs (Siche et al. 2010).

Proteobacteria

CbiMNOQ of Salmonella typhimurium
CbiM (M) (Q05594)
CbiN (Essential auxillary subunit) (Q05595)
CbiO (C) (Q05596)
CbiQ (M) (Q05598)
3.A.1.19:  The Thiamin Uptake Transporter (ThiT) Family (Most similar to 3.A.1.10, 3.A.1.6 and 3.A.1.8 in that order)
3.A.1.19.1









Thiamin, thiamin monophosphate and thiamin pyrophosphate porter. The 2.25 Å structure of ThiB (TbpA) has been solved (Soriano et al., 2008).
Proteobacteria
ThiBPQ of Salmonella typhimurium (functionally characterized and partially sequenced) and E. coli (fully sequenced but not functionally characterized)
ThiB; TbpA (R)
ThiP; YabK (M)
ThiQ; YabJ (C)
3.A.1.19.2









The thiamine pyrophosphate (TPP) uptake porter (Bian et al., 2011).

Bacteria

TPP transporter of Treponena denticola TDE0143/TDE0144/TDE0145
TDE0143 (R) (Q73RE6)
TDE0144 (M) (Q73RE5)
TDE0145 (C) (Q73RE4)
3.A.1.19.3









ABC transporter of unknown function. The three genes encoding this system are adjacent to a gene homologous to a mycothiol maleylpyruvate isomerase.

Actinobacteria

ABC transporter of Streptomyces hygroscopicus
Periplasmic binding protein (R) (H2JXL4)
Permease (M) (H2JXL5)
ATPase (C) (H2JXL6)
3.A.1.19.4









The putative sulfate/thiosulfate transporter, YnjBCD. YnjB has 12 TMSs. The three genes encoding this system are adjacent to one encoding a thiosulfate:sulfur transferase or a rhodanese (B7L6N1).

γ-Proteobacteria

YnjBCD of E. coli
YnjB (possible receptor, R) (B7L6M8)
YnjC (M) (B7L6M9)
YnjD (C) (B7L6N0)
3.A.1.19.5









Putative ABC transporter

Deinococcus-Thermus

ABC transporter of Deinococcus deserti
Permesae (M) (C1CWI2)
ATPase (C) (C1CWI3)
Possible periplasmic receptor (R) (C1CWI4)
3.A.1.20:  The Brachyspira Iron Transporter (BIT) Family (Most similar to 3.A.1.6, 3.A.1.8 and 3.A.1.11)
3.A.1.20.1









The iron transporter, BitABCDEF
Spirochaetes
BitABCDEF of Brachyspira (Serpulina) hyodysenteriae
BitA (R)
BitB (R)
BitC (R)
BitD (C)
BitE (M)
BitF (M)
3.A.1.21:  The Siderophore-Fe3+ Uptake Transporter (SIUT) Family
3.A.1.21.1









The Fe3+-Yersiniabactin uptake transporter, YbtPQ (Brem et al., 2001; Fetherston et al., 1999)
Proteobacteria
YbtPQ of Yersinia pestis
YbtP (M-C)
YbtQ (M-C)
3.A.1.21.2









The Fe3+-carboxymycobactin transporter, IrtAB (Rodriguez and Smith, 2006). IrtA contains an FAD-binding domain (Ryndak et al., 2010).

Actinobacteria
IrtAB of Mycobacterium tuberculosis
IrtA (M-C) (P63391)
IrtB (M-C) (P63393)
3.A.1.22:  The Nickel Uptake Transporter (NiT) Family
3.A.1.22.1









Nickel (Ni2+) porter
Proteobacteria
CbiKMQO of Actinobacillus pleuropneumoniae
CbiK (R)
CbiM (M)
CbiQ (M)
CbiO (C)
3.A.1.23:  The Nickel/Cobalt Uptake Transporter (NiCoT) Family
3.A.1.23.1









Nickel (Ni2+) porter (Chen and Burne, 2003)

Firmicutes

UreMQO of Streptococcus salivarius
UreM (M) (Q79CJ1)
UreQ (M) (Q79CJ0)
UreO (C) (Q79CI9)
3.A.1.23.2









Putative cobalt (Co2+) porter (Chen and Burne, 2003)
Firmicutes
CbiMQOK of Clostridium acetobutylicum
CbiM (M) (AAK79333)
CbiQ (M) (AAK79335)
CbiO (C) (AAK79336)
CbiK (Auxiliary?) (AAK79334)
3.A.1.23.3









Cobalt (Co2+) porter 

δ-Proteobacteria

Cbi M(N)OQ of Geobacter sulfurreducens 
Cbi M(N) (D7AE13)
CbiO (D7AE10)
CbiQ (D7AE11) 
3.A.1.24:  The Methionine Uptake Transporter (MUT) Family (Similar to 3.A.1.3 and 3.A.1.12)
3.A.1.24.1









The L- and D-methionine porter (also transports formyl-L-methionine) (Zhang et al., 2003). The 3.7A structure of MetNI has been solved. An allosteric regulatory mechanism operates at the level of transport activity so increased intracellular levels of the transported ligand stabilize an inward-facing, ATPase-inactive state of MetNI to inhibit further ligand translocation into the cell (Kadaba et al., 2008).
Proteobacteria
MetNIQ (abc-yaeE-yaeC) of E. coli
MetN (C) AAC73310
MetI (M) AAC73309
MetQ (R) AAC73308
3.A.1.24.2









The L- and D-methionine porter (also transports methionine sulfoxide (Hullo et al., 2004)
Firmicutes
MetNPQ (YusCBA) of Bacillus subtilis
MetN (C) CAB15264
MetP (M) CAB15263
MetQ (R) CAB15262
3.A.1.24.3









The methionine porter, AtmBDE (Sperandio et al., 2007)
bacteria
AtmBDE of Streptococcus mutans
AtmB (R) (Q8K8K9)
AtmD (C) (Q8K8K8)
AtmE (M) (Q8K8K7)
3.A.1.24.4









L-Methionine uptake porter, MetQNI

Bacteria

MetQNI of Corynebacterium glutamicum
MetQ (R) (Q8NSN1)
MetN (C) (Q8NSN2)
MetI (M) (Q8NSN3)
3.A.1.24.5









L-Histidine uptake porter, MetIQN (Johnson et al. 2008)

Proteobacteria

MetIQN of Pseudomonas aeruginosa
MetI (M) (Q9HT69)
MetQ (R) (Q9HT68)
MetN (C) (Q9HT70)
3.A.1.25:  The Biotin Uptake Transporter (BioMNY) Family
3.A.1.25.1









The biotin uptake porter (binding receptor lacking) (see also the VUT or ECF family; BioY; 2.A.88.1.1) (Rodionov et al., 2006; Hebbeln et al., 2007). BioN (the EcfT component of the biotin transporter) appears to be required for intramolecular signaling and subunit assembly (Neubauer et al., 2009). The Ala-Arg-Ser and Ala-Arg-Gly signatures in BioN are coupling sites to the BioM ATPases (Neubauer et al., 2011).  Subunit stoicheometries have been estimated with the prediction that there are oligomeric forms of BioM and BioY in the BioMNY complex (Finkenwirth et al. 2010).

Bacteria

BioMNY of Rhizobium etli
BioM (C) (226 aas; 0 TMSs; Q6GUB2)
BioN (M) (202 aas; 5 TMSs; Q6GUB1)
BioY (M) (189 aas; 6 TMSs; Q6GUB0)
3.A.1.25.2









Putative biotin Ecf transporter, EcfSAA'T (function assigned based on genome context analyses). 

Archaea

Putative Ecf transporter, EcfSAA'T, of Methanospirillum hungatei 
EcfS (M) (Q2FUL6)
EcfA (C) (Q2FUL5)
EcfA' (C) (Q2FUM0)
EcfT (M) (Q2FNH6) 
3.A.1.25.3









Putative biotin Ecf transporter, EcfSAA'T (function assigned based on genome context analyses).

Archaea

The putative EcfSAA'T transporter of Methanocorpusculum labreanum
Ecf5 (A2SPQ3)
EcfA (A2SPQ4)
EcfA' (A2SPQ5)
EcfT (A2SPQ6) 
3.A.1.25.4









The biotin uptake system, BioMNY. The 3-d structure of the EcfS subunit, BioY, at 2.1Å resolution is known (Berntsson et al., 2012). BioY and ThiT from L. lactis show similar N-terminal structures for interaction with the ECF module but divergent C-terminal structures for substrate binding. BioY alone binds biotin but doesn''t transport it (Berntsson et al., 2012).  Ala-Arg-Ser and Ala-Arg-Gly signatures in BioN are probably coupling sites to the two BioM ATPase subunits (Neubauer et al., 2011Neubauer et al., 2011).

Bacteria

BioMNY of Lactococcus lactis 
BioM (A) (A2RI01)
BioN (T) (A2RI03)
BioY (S) (A2RMJ9) 
3.A.1.25.5









Biotin/Riboflavin ECF transport system, EcfAA'T/RibU/BioY (Karpowich and Wang 2013).

Bacteria

EcfAA''T/RibU/BioY of Thermatoga martima
EcfA (C) (Q9WY65)
EcfA'' (C) (Q9X1Z1)
EcfT (M) (Q9X2I1)
BioY (M) (Q9X1G6)
RibU (M) (Q9WZQ6)
3.A.1.25.6









Riboflavin ECF transport system, EcfAA'T/RibU (Karpowich and Wang 2013).

Bacteria

EcfAA'T/RibU of Streptococcus thermophilus 
EcfA (C) (Q5M244)
EcfA' (C) (Q5M243)
EcfT (M) (Q5M245)
RibU (M) (Q5M614)
3.A.1.26:  The Putative Thiamine Uptake Transporter (ThiW) Family
3.A.1.26.1









The putative ABC porter (COG4732), ThiW; 718 aas; 5 TMSs; domain order: M-C-C; plus the putative ATPase binding subunit, CbiQ homologue (binding receptor unknown) (Rodionov et al., 2009)

Bacteria

ThiW/CbiQ of Chloroflexus aurantiacus
ThiW MCC (SAA) (A9WGB0)
CbiQ M (T) (A9WGA9)
3.A.1.26.2









ThiW homologue/CbiQ homologue (ThiW: 647 aas; M-C-C; 5-6TMSs) (Rodionov et al., 2009)

Archaea

ThiW/ChiQ of Methanocorpusculum labreanum
ThiW MCC (SAA) (A2SPE8)
CbiQ M (T) (A2SPE9)
3.A.1.26.3









ThiW homologue (711 aas; M-C-C) (No known binding receptor) plus a CbiQ homologue (Rodionov et al., 2009)

Bacteria

ThiW/CbiQ homologues of Actinomyces odontolyticus
ThiW MCC (SAA) (A7BAX2)
CbiQ M (T) (A7BAX3)
3.A.1.26.4









ThiW/CbiQ homologues (ThiW: 697 aas; M-C-C) (No known binding receptor) (Rodionov et al., 2009)

Bacteria

ThiW/CbiQ homologues of Mycobacterium tuberculosis
ThiW MCC (SAA) (P63399)
CbiQ M (T) (P64997)
3.A.1.26.5









ThiW/CbiQ/CbiO homologues (ThiW: 174 aas; 5 putative TMSs) (Rodionov et al., 2009)

Bacteria

ThiW/CbiQ/CbiO homologues of Roseiflexus castenholzii
ThiW (M) (S) (A7NRF9)
CbiQ (M) (T) (A7NRG1)
CbiO C-C (A-A) (A7NRG0)
3.A.1.26.6









The ThiW/CbiQ/CbiO1/CbiO2 homologues (ThiW: 184 aas; 1-6 TMSs) (Rodionov et al., 2009)

Archaea

ThiW/CbiQ/CbiO1/CbiO2 homologues of Aeropyrum pernix
ThiW M (S) (Q9Y974)
CbiQ M (T) (Q9Y982)
CbiO1 C (A) (Q9Y979)
CbiO2 C (A) (Q9Y977)
3.A.1.26.7









The putative hydroxyethyl thiazole (biosynthetic precursor of thiamine) porter, ThiW-EcfA1-A2-EcfT (this is a group II ECF transporter which uses a universal energy-coupling module (EcfA1-EcfA2-EcfT) in many firmicutes; Rodionov et al., 2002).

Bacteria

ThiW-EcfA1-EcfA2-EcfT of Enterococcus faecalis
ThiW (M) (Q830K3)
EcfA1 (C) (Q839D5)
EcfA2 (C) (Q839D4)
EcfT (M) (Q839D3)
3.A.1.26.8









Putative biotin Ecf transporter, EcfSAT

Archaea

Putative Ecf transpoter, EcfSAT, of Archaeoglobus fulgidus 
S-subunit (M) (O29098) 
A-subunit (C) (O29097) 
T-subunit (M) (O29096) 
3.A.1.26.9









The folate transporter, FolT/EcfAA''T (The 3-d structure is known to 3.0Å resolution (Xu et al. 2013; 4HUQ).  This transporter uses the same ECF energy coupling complex (AA''T) as 3.A.1.28.2.

Firmicutes

FolT/EcfAA'T of Lactobacillus brevis
FolT (M) (Q03S56)
EcfA (C) (Q03PY6)
EcfA' (C) (Q03PY7)
EcfT (M) (Q03PY5)
3.A.1.27:  The γ-Hexachlorocyclohexane (HCH) Family (Similar to 3.A.1.12 and 3.A.1.24)
3.A.1.27.1









The γ-hexachlorocyclohexane (γHCH) uptake permease, LinKLMN (most similar to 3.A.1.12.4, the QAT family) (Endo et al., 2007)
Bacteria
LinKLMN of Sphingobium japonicum
LinK (M) (BAF51698)
LinL (C) (BAF51699)
LinM (R) (BAF51700)
LinN (lipoprotein) (BAF51701)
3.A.1.27.2









The chloroplast lipid (trigalactosyl diacyl glycerol (TDG)) transporter, Tdg1,2,3 (Lu et al., 2007). Lipids such as mono- and digalactolipids are synthesized in the endoplasmic reticulum (ER) of plant cells and transferred to the thylakoid membranes of chloroplasts. Mutations in an outer chloroplastic envelope protein with 350 aas and 7 putative TMSs in the last 250 residues may catalyze translocation as part of a lipid transfer complex (Xu et al., 2003; Roston et al. 2012).

Plant Chloroplast

Tdg 1,2,3 of Arabidopsis thaliana:
Tdg1 (M) (Q8L4R0)
Tdg2 (R) (Q3EB35)
Tdg3 (C) (Q9AT00)
3.A.1.27.3









ABC transporter maintaining outer membrane (OM) lipid asymmetry, MlaABCDEF (Malinverni and Silhavy, 2009). MlaA (VacJ) is a "spreading" protein, essential for Shigella pathogenicity (Suzuki et al., 1994).

Actinobacteria

MlaABCDEF of E. coli
MlaA, OM lipoprotein component (251aas) (P76506)
MlaB, cytoplasmic STAS component (97aas) (P64602)
MlaC, periplasmic binding receptor (R) (211aas) (P0ADV7)
MlaD, anchored periplasmic binding receptor (R) (183aas) (P64604)
MlaE, inner membrane permease component (M) (260aas) (P64606)
MlaF, ATP binding protein (C) (269aas) (P63386)
3.A.1.27.4









The cholesterol uptake porter (Mohn et al., 2008). Takes up cholesterol, 5-α-cholestanol, 5-α-cholestanone, β-sitosterol, etc. (It is not established that all of these proteins comprise the system or that other gene products are not involved.)

Actinobacteria

Cholesterol uptake porter of Rhodococcus jostii
YrbE4A (ro04696; 254aas; 5-6 TMSs) (M) (Q0S7K4)
YrbE4B (ro04697; 283aas; 5 TMSs) (M) (Q0S7K3)
MceE4A (ro04698; 391aas; 1 N-terminal TMS) (R) (Q0S7K2)
MceE4B (ro04699; 338aas; 1 N-terminal TMS) (R) (Q0S7K1)
MlkA (ro01974; 363aas; 0 TMSs) (C) (Q0SFA1)
MlkB (ro01744; 346aas; 0 TMSs) (C) (Q0SD37)  
3.A.1.27.5









The Mce/Yrb/Mlk (Mammalian cell entry) ABC-type putative steroid uptake transporter (involved in several aspects of mycobacterial pathogenesis) (Mohn et al., 2008; Joshi et al., 2006).

Bacteria

The Mce transporter of Mycobacterium tuberculosis H37Rv
YrbE4A (M) (254aas; 6 TMSs) (O53546)
YrbE4B (M) (280aas; 5 TMSs) (O53545)
MceA (R) (242aas; 1 TMS) (O06356)
MceB (R) (244aas; 1 TMS) (O07422)
Mlk (C) (Mkl; MceG; 359aas; 0 TMSs) (P63357)
3.A.1.28:  The Queuosine (Queuosine) Family
3.A.1.28.1









The putative queuosine uptake transporter, QrtTUVW (Rodionov et al., 2009) (most similar to 2.A.88.2.1)

Bacteria

QrtTUVW of Salmonella enterica su. typh.
QrtT (M) (Q8XGV9)
QrtU (M) (Q8Z3V9)
QrtV (C) (Q8Z3V8)
QrtW (C) (Q8Z3V7)
3.A.1.28.2









The folate transporter, FolT/EcfAA''T (The 3-d structure is known to 3.0Å resolution (Xu et al. 2013; 4HUQ)

Firmicutes

EcfAA'ST of Lactobacillus brevis
EcfA (C) (Q03PY5)
EcfA' (C) (QO3PY6)
EcfS (M) (QO3NM0)
EcfT (M) (Q03PY7)
3.A.1.29:  The Methionine Precursor (Met-P) Family
3.A.1.29.1









The putative methionine precursor/uptake transporter, MtsTUV (T is most similar to 3.A.1.23.2; U is most similar to 2.A.36.7.1 and 3.A.1.14.2; V is most similar to 3.A.1.23.2 and 3.A.1.25.1) (Rodionov et al., 2009)

Bacteria

MtsTUV of Lactobacillus johnsoni
MtsT (M) (Q74I63)
MtsU (C) (Q74I62)
MtsV (M) (Q74I61)
3.A.1.30:  The Thiamin Precursor (Thi-P) Family
3.A.1.30.1









The putative thiamin precursor uptake transporter, YkoEDC (Rodionov et al., 2009) (E is most similar to 3.A.1.4.3; D is most similar to 3.A.1.26.2; C is most similar to 3.A.1.23.2).

Bacteria

YkoEDC of Bacillus subtilis
YkoE (M) (O34738)
YkoD (C-C) (O34362)
YkoC (M) (O34572)
3.A.1.30.2









Putative thiamin transporter

Firmicutes

Potential thiamin transporter of Streptococcus pneumoniae 
Membrane Protein 1 (Q97RJ2) 
ABC ATPase (Q97RS3)
Membrane Protein 2 (Q97RS4) 
3.A.1.31:  The Unknown-ABC1 (U-ABC1) Family
3.A.1.31.1









The putative uptake transporter of unknown substrate specificity, HtsTUV (Rodionov et al., 2009)

Bacteria

HtsTUV of Bifidobacterium longum
HtsT (M) (Q8G6E7)
HtsU (M) (Q8G6E8)
HtsV (C-C) (Q8G6E9)
3.A.1.31.2









EcfSTAA of unknown function.

Bacteria

EstSTA of Treponema denticola
EstS (Q73JF1)
EstT  (Q73JF2)
EstAA  (Q73JF3)  
3.A.1.32:  The Cobalamin Precursor (B12-P) Family
3.A.1.32.1









The putative cobalamin precursor uptake transporter, CbrTUV (Rodionov et al., 2009) (CbrT is most similar to 2.A.1.15.1; CbrU is most similar to 3.A.1.26.1 (MFS; e-4); CbrV is most similar to 2.A.53.11.1 and 3.A.1.2.2 (score of 0.035)) (CbrT has 6 putative TMSs; CbrV has 8-10 putative TMSs).

Bacteria

CbrTUV of Streptomyces coelicolor
CbrT (M) (Q9KXJ5)
CbrU (C-C) (Q9KXJ6)
CbrV (M) (Q9KXJ7)
3.A.1.32.2









Putative vitamin transporter, EcfSTAA

Archaea

Putative vitamin transporter of Methanosphaera stadtmanae, EcfSTAA'
EcfT (M) (Q2NFA7)
EcfA-A' (C) (Q2NFA8)
EcfS (M) (Q2NFA9) 
3.A.1.33:  The Methylthioadenosine (MTA) Family
3.A.1.33.1









The putative methylthio adenosine uptake transporter (Rodionov et al., 2009).  MtaTUV (MtaT and MtaU are most similar to 3.A.1.26.1 (ThiW); MtaV is most similar to 3.A.1.25.1 (BioN) and 3.A.1.23.2 (CbiQ)).

Bacteria

MtaTUV of Thermoanaerobacter tengcongensis
MtaT (M) (Q8R9M1)
MtaU (C-C) (Q8R9L8)
MtaV (M) (Q8R9L9)
3.A.1.34:  The Tryptophan (TrpXYZ) Family
3.A.1.34.1









The putative tryptophan uptake transporter, TrpXYZ. Regulated by tryptophan-specific T-box (Vitreschak et al. 2008)

Bacteria

TrpXYZ of Streptococcus pyogenes
TrpX (R) (Q99ZY6)
TrpY (M) (Q99ZY4)
TrpZ (C) (Q99ZY3)
3.A.1.35:  The Cobalamin Precursor/Cobalt (CPC) Family

The putative cobalamin precursor/cobalt (CPC) transporter family includes proteins of about 190 aas with 4-6 TMSs.  These proteins are encoded in operons that are subject to regulation by vitamin B12 (Rodionov et al., 2003), which is similar to members of 3.A.1.32; however, members of these two families show divegent sequences.  They are found in chloroflexi, cyanobacteria, and Firmicutes. Their functions have not been characterized.

 

3.A.1.35.1









Putative ECF transporter, EcfSTA; regulated by a cobalamin riboswitch.

Bacteria

EcfSTA of Roseifluxes sp. RS-1
EcfS (S) (A5UXW2)
EcfT (T) (A5UXW1)
EcfA (A) (A5UXW0) 
3.A.1.35.2









Putative Co2+ ECF transporter, EcfSTA

Bacteria

EcfSTA of Gloeobacter violaceus 
EcfS (S) (Q7NIY0)
EcfT (T) (Q7NIX9)
EcfA (A) (Q7NIX8) 
3.A.1.35.3









Putative Co2+ ECF transporter, EcfSTA

Bacteria

EcfSTA of Syntrophobotulus glycolicus
EcfS (S) (F0SWZ4)
EcfT (T) (F0SWZ5)
EcfA (A) (F0SWZ6) 
3.A.1.101:  The Capsular Polysaccharide Exporter (CPSE) Family
3.A.1.101.1









Capsular polysaccharide exporter
Gram-negative bacteria
KpsMT of E. coli KpsM
KpsM (M) - (P24584)
KpsT (C) - (P24586)
3.A.1.101.2









Vi polysaccharide exporter, VexBC (Hashimoto et al, 1993).
Gram-negative bacteria
VexBC of Salmonella typhi
VexB (M) - (P43109)
VexC (C) - (P43110)
3.A.1.101.3









Capsular polysialate exporter, CtrC/D (functions with 1.B.18.2.3 (OMA) and 1.B.4.2.1 (MPA2)) (Larue et al., 2011).

Bacteria

CtrABCD of Neisseria meningitidis
CtrC (M) (B3FHE1)
CtrD (C) (B3FHE0) 
3.A.1.102:  The Lipooligosaccharide Exporter (LOSE) Family
3.A.1.102.1









Lipooligosaccharide exporter (nodulation proteins, NodIJ)
Gram-negative bacteria
NodIJ of Rhizobium galegae
NodJ (M)
NodI (C)
3.A.1.103:  The Lipopolysaccharide Exporter (LPSE) Family
3.A.1.103.1









Lipopolysaccharide exporter
Gram-negative bacteria
RfbAB of Klebsiella pneumoniae
RfbA (M)
RfbB (C)
3.A.1.103.2









Heteropolysaccharide O-antigen exporter (Feng et al., 2004). The C-terminal cytoplasmic domain of Wzt (a IgG-like β-sandwich) determines the specificity of the transporter for either O8 or O9a O-PS (Cuthbertson et al., 2007).

Gram-negative bacteria

Wzm/Wzt of E. coli
Wzm (M) (AAS99164)
Wzt (C) (AAS99165)
3.A.1.104:  The Teichoic Acid Exporter (TAE) Family
3.A.1.104.1









Teichoic acid exporter, TagGH.  Appears to be present in a large complex with the teichoic acid precursor synthetic enzymes (Formstone et al. 2008).  The substrate may be the diphospholipid linked disaccharide portion of the teichoic acid precursor (Schirner et al. 2011).

Gram-positive bacteria

TagGH of Bacillus subtilis
TagG (M)
TagH (C)
3.A.1.104.2









The teichoic acid exporter, TarGH. May be specific for the diphospholipid linked disaccharide portion of the teichoic acid precursor (Schirner et al. 2011). TarG is the target of a small antimicrobial inhibitor of S. aureus growth (Swoboda et al. 2009).

Firmicutes

TarGH of Staphylococcus aureus 
TarG (M) (D1GQ18)
TarH (C) (D1GQ17) 
3.A.1.105:  The Drug Exporter-1 (DrugE1) Family
3.A.1.105.1









Daunorubicin; doxorubicin (drug resistance) exporter
Gram-positive bacteria
DrrAB of Streptomyces peucetius
DrrA (C)
DrrB (M)
3.A.1.105.2









Oleandomycin (drug resistance) exporter
Gram-positive bacteria
OleC4-OleC5 of Streptomyces antibioticus
OleC4 (C)
OleC5 (M)
3.A.1.105.3









The 4A-4E-O-dideacetyl-chromomycin A3 (biosynthetic precursor of chromomycin) exporter (may also export chromomycin and mithramycin (Menendez et al., 2007).
Gram-positive Bacteria
CmrAB of Streptomyces greseus
CmrA(C) (Q70J75)
CmrB(M) (Q70J76)
3.A.1.105.4









The pyoluteorin efflux pump, PltHIJKN

γ-Proteobacteria

PltHIJKN of Pseudomonas sp. M18:
PltH (336aas; MFP) - (Q4VWD0)
PltI (589aas; C-C) - (Q4VWC9)
PltJ (377aas; M; COG0842; similar to 9.B.74.2 (ABC-2)) - (Q4VWC8)
PltK (372aas; M; The C-terminal hydrophobic half has 5TMSs and is most similar to PltJ, and then to 9.B.74.2, but it is also homologous to 3.A.1.105.2 and 3.A.1.102.1) - (Q4VWC7)
PltN (480aas; OMF) - (Q4VWC6)
3.A.1.105.5









AbcG homologue

Animals

AbcG homologue of Drosophia melanogaster
3.A.1.105.6









The ABC-2-like transporter

Bacteria

ABC-2-like transporter of Dehalococcoides ethenogenes
ABC2 protein (M) (Q3Z8A7)
ATPase (C) (Q3Z8A8)
3.A.1.105.7









Putative ABC2 tranport system, SagGHI; may export streptolysin S.

Firmicutes

Putative Streptolysin ABC2 tranport system, SagGHI.
SagG (C) (Q9A0K0)
SagH (M) (Q9A0J9)
SagI (M) (Q9A0J8)
3.A.1.105.8









ABC-2 transporter.  The two genes encoding this system are adjacent to one encoding an squalene-hopene cyclase that coverts squalene to hopene.  The substrate could therefore be hopene or a hydrocarbon triterpene derivative of it (Racolta et al. 2012).

Planctomycetes

ABC2 membrane protein (Q7UE57) and ATPase (Q7UE58) of Rhodopirellula baltica
3.A.1.105.9









ABC2 membrane proteins (J7ZHK9 and J8A8S6) with ATPase (J8ABC0) transporter

Firmicutes

ABC2 transporter of Bacillus cereus
3.A.1.105.10









AbcG homologue

Animals

AbcH of Danio rerio (F1QZ58)
3.A.1.105.11









ABC-2 transporter probably specific for a lantibiotic.  The genes for this system are adjacent to an S2P-M50 peptidase (G0Q3D2), probably involved in pro-lantibiotic processing, as well as a lantibiotic biosynthetic enzyme (G0Q3D1) and a lantibiotic dehydratase (G0Q3D0). 

Actinobacteria

ABC-2/ATPase of Streptomyces griseus
ABC-2 (M) (G0Q3D4)
ATPase (C) (G0Q3D3)
3.A.1.105.12









ABC-2 transporter with ABC ATPase

Archaea

ABC transporter
ABC2 (M) (F8D412)
ABC ATPase (C) (F8D413) 
3.A.1.106:  The Lipid Exporter (LipidE) Family
3.A.1.106.1









Phospholipid, LPS, lipid A and drug exporter (flippase) (Eckford and Sharom, 2010). MsbA (essential for export to the outer membrane). MsbA also confers drug resistance to azidopine, daunomycin, vinblastine, Hoechst 33342 and ethidium (Reuter et al., 2003). Four x-ray structures, trapped in different conformations, two with and two without nucleotide, have been solved (Ward et al., 2007). They suggest an alternating accessibility mode of transport with major conformational changes.

Gram-negative bacteria

MsbA (M-C) of E. coli
3.A.1.106.2









The homodimeric Sav1866 multidrug exporter (transports doxorubicin, verapamil, ethidium, tetraphenylphosphonium, vinblastine and the fluorescent dye, Hoechst 33342; 3-D structure known at 3 Å resolution; Dawson and Locher, 2006; Velamakanni et al., 2008) The empty site opens by rotation of the nucleotide-binding domain whereas the ATP-bound site remains occluded (Jones and George, 2011). Conformational changes induced by ATP-binding and hydrolysis have been proposed (Becker et al. 2010; Becker et al. 2010; Oliveira et al., 2011). 

Gram-positive Bacteria

Sav1866 of Staphylococcus aureus (M-C) 2HYDA/2HYDB (578 aas)
3.A.1.106.3









The dimeric multidrug resistance exporter, ABC1/2 (exports the peptide antimicrobrials, nisin and polymyxin; (Margolles et al., 2006) (both ABC1 and ABC2 also show striking similarity to family 3.A.1.117).
Gram-positive Bacteria
ABC1/2 of Brevibacterium longum:
ABC-1 (M-C) (ZP_00121338)
ABC-2 (M-C) (ZP_00121339)
3.A.1.106.4









The duplicated ABC transporter, CgR_1214 (1247 aas; MC(poorly conserved) MC(well conserved))
Bacteria
CgR_1214 of Corynebacterium glutamicum (MCMC) (A4QD95)
3.A.1.106.5









The heterodimeric multidrug efflux pump, SmdAB (exports norfloxacin, tetracycline, 4',6-diamidino-2-phenylindole (DAPI), and Hoechst 33342) (Matsuo et al., 2008).
Bacteria
SmdAB of Serratia marcescens:
SmdA (M-C) (A7VN01)
SmdB (M-C) (A7VN02)
3.A.1.106.6









Multidrug efflux pump, Rv0194 (exports & causes resistance to ampicillin, streptomycin and chloramphenicol by 32- to 64-fold and to vancomycin and tetracycline by 4- to 8-fold (Danilchanka et al., 2008)).
Bacteria
Rv0194 of Mycobacterium tuberculosis (MCMC) (O53645)
3.A.1.106.7









The Salmochelin/Enterobactin secretory exporter, IroC (Crouch et al., 2008).
Bacteria
IroC of Salmonella enterica (MCMC) (Q8RMB7)
3.A.1.106.8









The heterodimeric BmrC/BmrD (YheHI) MDR transporter.  Transports a wide range of structurally unrelated drugs including doxyrubicin, mitoxantrone, ethidium, and hoechst 33342 (Torres et al., 2009). It activates the sensor kinase, KinA, during sporulation initiation (Fukushima et al. 2006). Large scale purification has been achieved (Galián et al. 2011).  It has been reconstituted in giant unilamellar vesicles (Dezi et al. 2013).

Bacteria

BmrC/BmrD (YheHI) of Bacillus subtilis
YheH (M-C) (O07549)
YheI (M-C) (O07550)
3.A.1.107:  The Putative Heme Exporter (HemeE) Family
3.A.1.107.1









Putative heme exporter, CcmABC=CycVWZ (Note: CcmC may function independently of CcmAB) (Feissner et al., 2006; Christensen et al., 2007)
Gram-negative bacteria
CycVWZ of Bradyrhizobium japonicum
CycV (C)
CycW (M)
CycZ (M)
3.A.1.107.2









The mitochondrial ABC transporter involved in cytochrome c maturation, CcmA/CcmB. (Note: CcmA is nuclearly encoded while CcmB is mitochondrially encoded) (Rayapuram et al., 2007)
Plant Mitochondria
CcmA/CcmB of Arabidopsis thaliana
CcmA (C) (Q9C8T1)
CcmB (M) (P93280)
3.A.1.107.3









CcmABCD exporter; CcmD (69aas, 1TMS) is required for the release of CcmE (which binds heme in the periplasm) from CcmABC. CcmC (9.B.14.2.3) is required for the transfer of heme to CcmE in the periplasm (Richard-Fogal et al., 2008) In the presence of heme, CcmC and CcmE form a stable complex (Richard-Fogal & Kranz, 2010).

Proteobacteria

CcmABCD of E. coli
CcmA (C) (Q8XE58)
CcmB (M; 7 TMSs) (P0ABM0)
CcmC (M; 6 TMSs) (P0ABM1)
CcmD (M; 1 TMS) (P0ABM7)
3.A.1.107.4









Cytochrome c maturation system (heme exporter?), CcmA/B

γ-Proteobacteria

CcmAB of Pseudomonas virdiflava
CcmA (C) (K6BJ24)
CcmB (M) (K6BIH6)
3.A.1.108:  The β-Glucan Exporter (GlucanE) Family
3.A.1.108.1









β-Glucan exporter
Gram-negative bacteria
NdvA (M-C) of Rhizobium meliloti
3.A.1.109:  The Protein-1 Exporter (Prot1E) Family
3.A.1.109.1









α-Hemolysin exporter. HlyB has an (inactive?) N-terminal C39 peptidase-like domain (Lecher et al., 2011).  It is essential for secretion and interacts with the unfolded HlyA, thereby protecting it from cytoplasmic degradation (Lecher et al. 2012).

Gram-negative bacteria

HlyB (M-C) of E. coli
3.A.1.109.2









Cyclolysin exporter, CyaB (Glaser et al., 1988) (Possesses an N-terminal lysosomal sorting signal within the amino-terminal transmembrane domain; Kamakura et al., 2008).

Gram-negative bacteria

CyaB (M-C) of Bordetella pertussis
3.A.1.109.3









LapA adhesin protein exporter, LapB (Hinsa et al., 2003)
Bacteria
LapB of Pseudomonas putida
LapB (MC) (AAN65800)
3.A.1.109.4









The biofilm inducible ABC-type drug resistance pumps, PA1875-PA1877 (Zhang and Mah, 2008).
Proteobacteria
PA1875-PA1877 of Pseudomonas aeruginosa
PA1875 (OMF; 425 aas) (Q9I2M2)
PA1876 (ABC; M-C; 723 aas) (Q9I2M1)
PA1877 (MFP; 395 aas) (Q9I2M0)
3.A.1.110:  The Protein-2 Exporter (Prot2E) Family
3.A.1.110.1









Microcin E492 exporter, MceFGH (MceF has 5 - 7 TMSs and is most likely a CAAX amino terminal protease that might function in the processing of microcin E492; MceG has a short hydrophilic N-terminus, a centra 6 TMS ABC domain, and a C-terminal ABC ATPase domain; MceH has 1 N-terminal TMS) (Bieler et al., 2006; Lagos et al., 1999)

Proteobacteria

MceGH of Klebsiella pneumoniae
MceG (C-M-C) (Q93GK5)
MceH (MFP) (Q93GK4)
3.A.1.110.2









Colicin V exporter
Enteric bacteria
CvaB (M-C) of E. coli
3.A.1.110.3









The multiple protein exporter, PrsD/PrsE (exports EPS glycanases, PlyA and PlyB, as well as Rhizobium adhering proteins) (Russo et al., 2006). 12 substrates have been identified; PrsDE provide the major route of protein export in R. leguminosarum (Krehenbrink and Downie, 2008).
Gram-negative bacteria
PrsD/PrsE of Rhizobium leguminosarum
PrsD(M-C) (O05693)
PrsE(MFP) (O05694)
3.A.1.110.4









Alkaline protease exporter
Gram-negative bacteria
AprD (M-C) of Pseudomonas aeruginosa
3.A.1.110.5









S-layer protein exporter
Gram-negative bacteria
RsaD (M-C) of Caulobacter crescentus
3.A.1.110.6









Exporter for lipase LipA, protease PrtA and S-layer protein SlaA, LipBCD (Akatsuka et al. 1997).   LipABC is also called PrtDEF.

Gram-negative bacteria

LipBCD of Serratia marcescens
LipB (M-C) (Q54456)
LipC (MFP) (Q54457)
LipD (OMF) (O87950)

3.A.1.110.7









Exporter for heme-binding protein, HasA and metaloprotease, PrtA.  Functions as a complex spanning the two membranes of the cell envelope: HasDEF (HasD = ABC protein; HasE = the MFP; HasF = the OMF (see 2.A.6.2.31 for HasF) (Akatsuka et al. 1997).

Gram-negative bacteria

HasDEF of Serratia marcescens
HasD (M-C) (Q53368)
HasE (MFP) (Q57387)
HasF (OMF) (Q54452)   
3.A.1.110.8









Surface layer protein exporter
Gram-negative bacteria
SapD (M-C) of Campylobacter fetus
3.A.1.110.9









Exporter of HasA lipase, and alkaline protease
Gram-negative bacteria
HasD (M-C) of Pseudomonas fluorescens
3.A.1.110.10









The AlgE-type Mannuronan C-5-Epimerase exporter, EexD (PrtD) (Gimmestad et al., 2006).
Bacteria
EexD of Azotobacter vinelandii (C1DS84)
3.A.1.110.11









Secretion system for metaloprotease, PrtA, PrtDEF (Akatsuka et al. 1997). (PrtF=1.B.17.1.2)

Gram-negative bacteria

PrtDEF of Erwinia chysanthemi 
PrtD (M-C) (P23596)
PrtE (MFP) (P23597) 
3.A.1.111:  The Peptide-1 Exporter (Pep1E) Family
3.A.1.111.1









Hemolysin/bacteriocin (cytolysin) exporter with associated proteolytic activity
Gram-positive bacteria
CylT (M-C) (CylB) of Enterococcus faecalis
3.A.1.111.2









Subtilin (toxic peptide) exporter
Gram-positive bacteria
SpaB (M-C) of Bacillus subtilis
3.A.1.111.3









Nisin exporter
Gram-positive bacteria
NisT (M-C) of Lactococcus lactis
3.A.1.111.4









Bacteriocin immunity protein, SmbG (198 aas; 6TMSs in a 2+2+2 arrangement. (Exports bacteriocins and causes resistance to antibiotics such as tetracycline, penicillin and triclosan). Upregulated by exposure to antibiotics (Matsumoto-Nakano and Kuramitsu, 2006)
Gram-positive bacteria
SmbG (M-C) of Streptococcus mutans (Q5TLL2)
3.A.1.111.5









The lacticin Q exporter, LcnDR3 (Yoneyama et al., 2009).

Gram-positive bacteria

LcnDR3 (M-C) of Lactococcus lactis (P37608)
3.A.1.111.6









Salivericin 9 exporter, SivT (692 aas; 6 TMSs) (Wescombe et al., 2011)

Firmicutes

SivT of Strepococcus salivarius (F8LI02)
3.A.1.112:  The Peptide-2 Exporter (Pep2E) Family
3.A.1.112.1









Competence factor (CSF; a heptadecapeptide) exporter. 

Gram-positive bacteria

ComA (M-C) of Streptococcus pneumoniae (functions with putative MFP accessory protein, ComB)
3.A.1.112.2









Pediocin PA-1 exporter
Gram-positive bacteria
PedD (M-C) of Pediococcus acidilactici
3.A.1.112.3









Bacteriocin (lactococcin) exporter. 

Gram-positive bacteria

LcnC (M-C) of Lactococcus lactis (functions with putative MFP accessory protein LcnD)
3.A.1.112.4









Sublancin exporter, SunT
Gram-positive bacteria
SunT (M-C) of Bacillus subtilis
3.A.1.112.5









Exporter of the BlpC peptide pheromone (B5E242) and several bacteriocins, BlpAB (Kochan and Dawid 2013).

Firmicute

BlpAB of Streptococcus pneumoniae
BlpA (M-C) (B3E244)
BlpB (MFP) (B3E242)
3.A.1.113:  The Peptide-3 Exporter (Pep3E) Family
3.A.1.113.1









Modified cyclic peptide (syringomycin) exporter, SyrD
Gram-negative bacteria
SyrD (M-C) of Pseudomonas syringae
3.A.1.113.2









Pyoverdin (siderophore) exporter
Gram-negative bacteria
PvdE (M-C) of Pseudomonas aeruginosa
3.A.1.113.3









The microcin J25 (21 aa cyclic peptide antibiotic) exporter, YojI (Delgado et al., 2005) (TolC is also required for export; Vincent and Morero, 2009). Also exports L-cysteine (Yamada et al., 2006).

Gram-negative bacteria

YojI of E. coli (P33941)
3.A.1.114:  The Probable Glycolipid Exporter (DevE) Family
3.A.1.114.1









Glycolipid exporter (under nitrogen control in heterocysts), DevABC-HgdD (Moslavac et al., 2007). Heterocyst envelope glycolipids (HGLs) function as an O2 diffusion barrier, being deposited over the heterocyst outer membrane, surrounded by an outermost heterocyst polysaccharide envelope. DevBCA and TolC form an ATP-driven efflux pump required for the export of HGLs across the Gram-negative cell wall (Staron et al., 2011). DevB, the MFP, must be hexameric to create a functional export complex.

Cyanobacteria

DevABC-HgdD of Anabaena variabilis (sp. strain PCC7120)
DevA (C)
DevB (MFP)
DevC (M)
HgdD (TolC like)
3.A.1.115:  The Na+ Exporter (NatE) Family
3.A.1.115.1









Na efflux pump NatAB

Gram-positive bacteria
NatAB of Bacillus subtilis
NatA (M)
NatB (C)
3.A.1.115.2









Putative Na extrusion pump, NatAB.  NatB has an N-terminal NatB domain (residues 1 - 375) as well as a C-terminal CAAX protease domain (9.B.2; residues 380 - 650).

Planctomycetes

NatAB of Rhodopirellula baltica
3.A.1.116:  The Microcin B17 Exporter (McbE) Family
3.A.1.116.1









Microcin B17 exporter
Enteric bacteria
McbEF of E. coli
McbE (M)
McbF (C)
3.A.1.117:  The Drug Exporter-2 (DrugE2) Family
3.A.1.117.1









The multidrug exporter, LmrA (can also substitute for MsbA [TC #3.A.1.106.1] to export lipid A; Reuter et al., 2003).
Gram-positive bacteria
LmrA (M-C) of Lactococcus lactis
3.A.1.117.2









Hop resistance protein, HorA.  Reconstitution in phosphatidyl ethanolamine bilayers resulted in normal activity, but reconstitution in phosphatidly choline resulted in uncoupling of ATP hydrolysis from transport and a change in the orientations of the TMSs (Gustot et al. 2010).

Gram-positive bacteria

HorA (M-C) of Lactobacillus brevis
3.A.1.118:  The Microcin J25 Exporter (McjD) Family
3.A.1.118.1









The cyclic peptide antibiotic, microcin J25 exporter, McjD (TolC is also required for export; Vincent and Morero, 2009).

Gram-negative bacteria

McjD (M-C) of E. coli
3.A.1.119:  The Drug/Siderophore Exporter-3 (DrugE3) Family
3.A.1.119.1









5-Hydroxystreptomycin and other streptomycin-like aminoglycoside exporter, StrVW
Gram-positive bacteria
StrVW of Streptomyces glaucescens
StrV (M-C)
StrW (M-C)
3.A.1.119.2









Tetracycline/oxytetracycline/oxacillin exporter, TetAB
Gram-positive bacteria
TetAB (StrAB) of Corynebacterium striatum
TetA (M-C)
TetB (M-C)
3.A.1.119.3









Exochelin exporter, ExiT
Gram-positive bacteria
ExiT of Mycobacterium smegmatis
(MC-M-C)
3.A.1.120:  The (Putative) Drug Resistance ATPase-1 (Drug RA1) Family
3.A.1.120.1









Macrolide ATPase (membrane constituent unknown)
Gram-positive bacteria
SrmB (C-C) of Streptomyces ambofaciens
3.A.1.120.2









Tylosin ATPase (membrane constituent unknown)
Gram-positive bacteria
TlrC (C-C) of Streptomyces fradiae
3.A.1.120.3









Oleandomycin resistance ATPase (membrane constituent unknown)
Gram-positive bacteria
OleB (C-C) of Streptomyces antibioticus
3.A.1.120.4









Carbomycin resistance ATPase (membrane constituent unknown)
Gram-positive bacteria
Carbomycin, CarA (C-C), protein of Streptomyces thermotolerans
3.A.1.120.5









The acetate resistance ABC acetate exporter (Nankano et al., 2006)
Gram-negative bacteria
AatA (C-C) of Acetobacter aceti (BAE71146)
3.A.1.120.6









The Uup protein (required for bacterial competitiveness (Murat et al., 2008); 39% identical to 3.A.1.120.5).

Gram-negative bacteria

Uup of E. coli (P43672)
3.A.1.121:  The (Putative) Drug Resistance ATPase-2 (Drug RA2) Family
3.A.1.121.1









Erythromycin ATPase (membrane constituent unknown)
Gram-positive bacteria
MsrA (C-C) of Staphylococcus epidermidis
3.A.1.121.2









Pristinamycin resistance protein, VgaG
Gram-positive bacteria
VgaB (C-C) of Staphylococcus aureus
3.A.1.121.3









Antibiotic (virginiamycin and lincomycin) resistance protein, VmlR
Gram-positive bacteria
VmlR (C-C) of Bacillus subtilis (P39115)
3.A.1.121.4









The two component ABC-4-type transporter (Rafii and Park, 2008).  Transports multiple drugs including ethidium and fluoroquinolones.

Bacteria and archaea

The ABC-4 M/C-C transporter of Clostridium hathewayi (Q83XH0)
(Q83XH1)
3.A.1.122:  The Macrolide Exporter (MacB) Family
3.A.1.122.1









Macrolide (14- and 15- but not 16-membered lactone macrolides including erythromycin) exporter, MacAB (both MacA and MacB are required for activity) (Tikhonova et al., 2007). MacAB also functions (probably with TolC) to export heat-stable enterotoxin II (Yamanaka et al., 2008). The crystal structure of MacA is available (Yum et al., 2009). MacB is a dimer whose ATPase activity and macrolide-binding capacity are regulated by the membrane fusion protein MacA (Lin et al., 2009). Xu et al. (2009) have reported the crystal structure of the periplasmic region of MacB. Also exports L-cysteine (Yamada et al., 2006). The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by the MacB transporter (Modali and Zgurskaya, 2011).

Gram-negative bacteria

MacAB of E. coli:
MacA(MFP) (P75830)
MacB(C-M) (P75831)
3.A.1.122.2









The SpdC antimicrobial peptide resistance efflux pump, YknWXYZ (Butcher and Helmann, 2006; Yamada et al., 2012). YknW interacts directly with YknXYZ.

Bacteria

YknWXYZ of Bacillus subtilis:
YknW (O31709)
YknX (MFP) (O31710)
YknY (C) (O31711)
YknZ (M) (O31712)
3.A.1.122.3









The enterocin AS-48 exporter, As-48FGH
Gram-positive bacteria
As-48FGH on plasmid pMBL of Enterococcus faecalis:
As-48F (MFP) (Q7AUQ4)
As-48H (M) (Q8RKC0)
As-48G (C) (Q8RKC1)
3.A.1.122.4









Probable Heme exporter, HrtAB (Stauff et al., 2008)
Bacteria
HrtAB of Staphylococcus aureus:
HrtA (C) (Q7A3X3)
HrtB (M) (Q7A7X2)
3.A.1.122.5









ABC transporter of unknown function (DUF214 protein) (4TMSs)/ABC protein [Msed1528/Msed1530]
Archaea
Msed1528/Msed1530 of Metallosphaera sedula (M) (A4YGY2)
3.A.1.122.6









ABC transporter of unknown function (DUF214 protein) (4TMSs)/ABC protein [MA2839/MA2840]
Archaea
MA2839/MA2840 of Methanosarcina acetivorans
MA2839 (M) (Q8TM31)
MA2840 (C) (Q8TM30)
3.A.1.122.7









ABC transporter of unknown function (Duf214 protein (409aas; 4TMSs:1+3)/ABC protein)
Archaea
Duf214 protein/ ABC protein of Methanococcus voltae:
Duf214 protein (M) (A8TDX0)
ABC protein (C) (A8TDW7)
3.A.1.122.8









Putative ABC3 permease, PC1,2,3.
Bacteria
PC1,2,3 of Treponema denticola:
PC1 (C) - Q73MJ2
PC2 (M) - Q73MJ3
PC3 (M) - Q73MJ4
3.A.1.122.9









Duf214 protein (405aas)/ ABC protein
Archaea
Duf214/ABC system of Caldivirga maquilingensis:
Duf214 protein (M) (A8M8Z1)
3.A.1.122.10









Duf214 (423aas)/ ABC system
Archaea
Duf214/ABC system of Sulfolobus tokodaii:
Duf214 protein (M) (Q973J4)
3.A.1.122.11









The hemin resistance transporter, HrtAB. Expression is activated by hemin or hemoglobin via the ChrAS transmembrane sensor kinase/response regulator system (Bibb and Schmitt 2010).

Bacteria

HrtAB of Corynebacterium diphtheriae
HrtA (C) (H2GZC3)
HrtB (M) (H2GZC4) 
3.A.1.122.12









Arthrofactin efflux pump, ArfDE (Balibar et al. 2005).

γ-Proteobacteria

ArfDE of Pseudomonas sp. MIS38
ArfD (MFP) (Q84BQ3)
ArfE (ABC) (A0ZUB1)
3.A.1.122.13









Putative ABC3-type antimicrobial peptide transporter, fused ATPase-porter protein, U-ABC3-1b (667aas; 4TMSs:1+3)
Bacteria
U-ABC3-1b of Lactobacillus brevis (CM) (Q03RZ6)
3.A.1.123:  The Peptide-4 Exporter (Pep4E) Family
3.A.1.123.1









Pep5 lantibiotic exporter, PepT

Gram-positive bacteria

PepT (M-C) of Staphylococcus epidermidis
3.A.1.123.2









Aureocin A70 multipeptide bacteriocin (AurA, AurB, AurC, AurD) exporter, AurT
Gram-positive bacteria
AurT (M-C) of Staphylococcus aureus
3.A.1.123.3









The one component lantibiotic exporter, GdmT (Sibbald et al., 2006)
Gram-positive bacterium
GdmT (M-C) of Staphylococcus gallinarum (A3QNP2)
3.A.1.124:  The 3-component Peptide-5 Exporter (Pep5E) Family
3.A.1.124.1









The 3-component nisin immunity exporter, NisFEG. Contains an essential E-loop (Okuda et al., 2010).

Gram-positive bacteria

NisFEG of Lactococcus lactis
NisF (C)
NisE (M)
NisG (M)
3.A.1.124.2









The 3-component subtilin immunity exporter, SpaEFG
Gram-positive bacteria
SpaEFG of Bacillus subtilis
SpaE (M)
SpaF (C)
SpaG (M)
3.A.1.124.3









The lantibiotic Nukacin ISK-1 (TC# 1.C.21.1.5)/NukH (BAD01013; 92aas) exporter, NukEFG (Okuda et al., 2008)
Gram-positive bacteria
NukEFG of Staphylococcus warneri
NukE (M) (Q75V14)
NukF (C) (Q75V15)
NukG (M) (Q75V13)
3.A.1.124.4









The macedocin exporter, McdEFG (Papadelli et al., 2007)
Gram-positive bacteria
McdEFG of Streptococcus macedonicus
McdE (M; 254 aas) (A6MER6)
McdG (M; 245 aas) (A6MER7)
McdF (C; 304 aas) (A6MER5)
3.A.1.124.5









The salivaricin exporter, SboEFG (Hyink et al., 2007)
Gram-positive bacteria
SboEFG of Streptococcus salivarius
SboE (M; 249 aas) (Q09IH9)
SboF (C; 303 aas) (Q09II0)
SboG (M; 242 aas) (Q09IH8)
3.A.1.125:  The Lipoprotein Translocase (LPT) Family
3.A.1.125.1









Lipoprotein translocation system (translocates lipoproteins from the inner membrane to periplasmic chaperone, LolA, which transfers the lipoproteins to an outer membrane receptor, LolB, which anchors the lipoprotein to the outer membrane of the Gram-negative bacterial cell envelope) (see 1.B.46; Narita et al., 2003; Ito et al., 2006; Watanabe et al., 2007). The structure of ligand-bound LolCDE has been solved (Ito et al., 2006). LolC and LolE each have 4 TMSs (1+3). Unlike most ATP binding cassette transporters mediating the transmembrane flux of substrates, the LolCDE complex catalyzes the extrusion of lipoproteins anchored to the outer leaflet of the inner membrane. The LolCDE complex is unusual in that it can be purified as a liganded form, which is an intermediate of the lipoprotein release reaction (Taniguchi and Tokuda, 2008). LolCDE has been reconstituted from separated subunits (Kanamaru et al., 2007).
Gram-negative bacteria
LolCDE of E. coli
LolC (M)
LolD (C)
LolE (M)
3.A.1.125.2









Putative lipoprotein LolCDE homologue LolCE (10TMSs:1+6+3)/LolD
Bacteria
LolCE/LolD of Mycobacterium tuberculosis
LolCE (M) (Q7D911)
LolD (C) (O53899)
3.A.1.125.3









Duf214 protein (843aas; 10TMSs:1+6+3)
Bacteria
Duf214 protein/ ABC protein of Frankia sp. CcI3:
Duf214 protein (M) - Q2J9P4
[LolD/FtsE/SalX]-type ABC protein (C) - Q2J9P5
3.A.1.126:  The β-Exotoxin I Exporter (βETE) Family
3.A.1.126.1









Exporter of β-exotoxin I, BerAB
Bacteria
β-exotoxin exporter, BerAB, of Bacillus thuringiensis
BerA (C)
BerB (M)
3.A.1.127:  The AmfS Peptide Exporter (AmfS-E) Family
3.A.1.127.1









Exporter of AmfS extracellular peptidic morphogen (Chater and Horinouchi, 2003; Ueda et al., 2002)
Bacteria
AmfS exporter, AmfAB of Streptomyces griseus
AmfA (MC) (BAA33537)
AmfB (MC) (BBA33538)
3.A.1.128:  The SkfA Peptide Exporter (SkfA-E) Family
3.A.1.128.1









Exporter of SkfA processed peptide (spO31422), SkfEF (González-Pastor et al., 2003)

Bacteria

SkfEF (YbdAB) of Bacillus subtilis
SkfE (C) O31427
SkfF (M-M) O31438
3.A.1.128.2









Putative ABC exporter, Teth 514-0346 & 0347

Bacteria

Teth 514-0346 & 0347 of Thermoanaerobacter sp. x514:
Teth514-0346 (C) (B0K2P2)
Teth514-0347 (M-M) (B0K2P3)
3.A.1.128.3









Putative ABC exporter, CLK2533/CLK2534

Bacteria

CLK2533/CLK2534 of Clostridium botulinum
CLK2533 (M-M) (B1L0U0)
CLK2534 (C) (B1L0U1)
3.A.1.128.4









Putative ABC exporter Tiet1371/1372

Bacteria

Tiet1371/72 of Thermotoga lettingae
Tiet1371 (M-M) (A8F6Z4)
Tiet1372 (C) (A8F6Z5)
3.A.1.129:  The CydDC Cysteine Exporter (CydDC-E) Family
3.A.1.129.1









Cysteine/Glutathione exporter, CydDC; CydC is also called MdrH (periplasmic cysteine is required for cytochrome bd assembly) (Cruz-Ramos et al., 2004)

Bacteria

CydDC of E. coli
CydD (M-C) (P29018)
CydC (M-C) (P23886)
3.A.1.130:  The Multidrug/Hemolysin Exporter (MHE) Family
3.A.1.130.1









The multidrug/hemolysin exporter, CylA/B (note: CylK (AAF01071) may influence its activity)(Gottschalk et al., 2006)
Bacteria
CylA/B of Streptococcus agalactiae
CylA (C) (Q9X432)
CylB (M) (Q9X433)
3.A.1.131:  The Bacitracin Resistance (Bcr) Family
3.A.1.131.1









The 2 or 3 component bacitracin-resistance efflex pump, BcrAB or BcrABC (Podlesek et al., 1995; Bernard et al., 2003) (BcrA is most similar to SpaF (3.A.1.124.2), but BcrB (5-6 TMSs) is only distantly related to other ABC2-type membrane proteins (Wang et al., 2009). BcrC is not sufficiently similar to detect similarity in BLAST searches. BcrC (5TMSs) belongs to the PAP2 phosphatase superfamily and may not be a contituent of the BcrAB transporter.

Bacteria

BcrABC of Bacillus licheniformis
BcrA (C) - (P42332)
BcrB (M) - (P42333)
3.A.1.131.2









Lantibiotic immunity system, LanEF. Contains an essential E-loop, a variant of the Q-loop, well conserved in nucleotide binding domains of lantibiotic exporters (Okuda et al., 2010).

Gram-positive bacteria

LanEF of Bacillus licheniformis
LanE (M) (Q65DD3)
LanF (C) (Q65DD1)
3.A.1.131.3









Transporter homologue, Tiet1372

Bacteria

Tiet1372 of Thermotoga lettingae (A8F6Z5)
3.A.1.132:  The Gliding Motility ABC Transporter (Gld) Family
3.A.1.132.1









The GldAFG putative ABC transporter required for ratchet-type gliding motility; may function in secretion of a macromolecule such as an exopolysaccharide. (Agarwal et al., 1997; Hunnicutt et al., 2002; McBride and Zhu 2013). Soluble GldG homologues (no TMSs) are found in eukaryotes (e.g. intraflagellar protein transpoMcBride and Zhu 2013). Soluble GldG homologues (no TMSs) are found in eukaryotes (e.g. intraflagellar protein transporter, IPT52 of Chlamydomonas reinhardtii; XP_001692161)

Bacteria

GldAFG of Flavobacterium johnsoniae:
GldA (C; 298 aas) - (O30489)
GldF (M; 241 aas; 6TMSs (2+2+2) - (Q93LN1)
GldG (M-periplasm; putative auxillary subunit with 2TMSs at the N and C-termini; 561 aas)- (Q93LN0).
3.A.1.132.2









The NosDFY Copper ABC transporter (Chan et al., 1997)
Bacteria
NosDFY of Sinorhizobium meliloti
NosD (R; periplasmic copper binding receptor)(Q52899)
NosF (C; like GldA) (Q52900)
NosY (M; like GldF) (O07330)
3.A.1.132.3









The uncharacterized ABC transporter with GldF-GldG homologues fused
Bacteria
GldAFG homologues of Magnetococcus sp. MC-1
GldFG (M-Aux; 964 aas) (A0L4K8)
GldA (C; 399 aas) (A0L4L0)
3.A.1.132.4









The uncharacterized ABC transporter with GldF-GldG homologues fused
Bacteria
GldAFG homologues of Hahella chejuensis
GldF-G (M-Aux; 978 aas) (Q2SDB0)
GldA (C; 315 aas) (Q2SDB1)
3.A.1.132.5









Putative ABC2 transporter: Membrane protein of 274aas and 6 TMSs; Cytoplasmic ATPase of 302aas.

Proteobacteria

Putative ABC2 transporter of Shewanella pealeana
(M) (A8GZV3)
(C) (A8GZV2) 
3.A.1.132.6









Putative ABC2 transporter: Membrane protein of 274aas and 6 TMSs; Cytoplasmic ATPase of 302aas.

Firmicutes

Putative ABC-2 transporter of Streptococcus pyogenes 
(M) (Q99ZC7)
(C) (Q99ZC8) 
3.A.1.132.7









Putative ABC membrane protein with 12 TMSs. (ATPase subunit unknown, and not encoded by an adjacent gene).

Planctomycetes

ABC membrane protein of Rhodopirellula baltica
3.A.1.132.8









ABC transporter, annotated as involved in multi copper protein maturation

Archaea

ABC exporter of Methanocella conradii
permease (M) (H8I780)
ATPase (C) (H8I779)
3.A.1.133:  The Peptide-6 Exporter (Pep6E) Family
3.A.1.133.1









The modified YydF* peptide exporter, YydIJ (Butcher et al., 2007)
Bacteria
YydIJ of Bacillus subtilis:
YydI (C) (Q45593)
YydJ (M) (Q45592)
3.A.1.133.2









A 6TMS homologue of YydJ (ORF1) of 280aas
Bacteria
ORF1 of Flavobacteria bacterium BBFL7 (Q26C21)
3.A.1.134:  The Peptide-7 Exporter (Pep7E) Family
3.A.1.134.1









The lantibiotic, salivericin A exporter, SalXY
Gram-positive bacteria
SalXY of Streptococcus salivarius
SalX (C)
SalY (M)
3.A.1.134.2









The bacitracin-resistance (putative bacitracin exporter), MbrAB. Participate with BreSR to control its own gene expression (Bernard et al., 2007).
Gram-positive bacteria
MbrAB of Streptococcus mutans
MbrA (C)
MbrB (M)
3.A.1.134.3









The bacitracin exporter, BceAB (BarAB; YtsCD) (Bernard et al., 2003; Ohki et al., 2003).  Functions in both signaling to the two component system, BceRS, and in export of the antimicrobial peptide.  Specific regions and residues are invollved in signalling or transport (Kallenberg et al. 2013).

Gram-positive bacteria

BceAB (YtsCD) of Bacillus subtilis
BceA (C) CAB15016
BceB (M) CAB15015
3.A.1.134.4









The bacitracin/vancoresmycin (a tetramic acid antibiotic) resistance exporter (Becker et al. 2009) (most like 3.A.1.134.2)

Firmicutes

SPR0812/SPR0813 of Streptococcus pnenmoiae
SPR0812 (C) (Q8DQ77)
SPR0813 (M) (Q8DQ76)
3.A.1.134.5









The MDR exporter, YvcRS. Possibly linked to regulation by a sensor kinase/response regulator system (YvcQP) (Joseph et al., 2002; Bernard et al., 2007).

Bacteria

YvcRS of Bacillus subtilis
YvcR (C) (O06980)
YvcR (M) (O06981)
3.A.1.134.6









The cationic peptide/MDR exporter, YxdLM. Possibly linked to a sensor kinase/reponse regulator system (YxdJK) (Joseph et al., 2002; Bernard et al., 2007).

Bacteria

YxdLM of Bacillus subtilis
YxdL (C) (P42423)
YxdM (M) (P42424)
3.A.1.134.7









The VraFG ABC transporter interacts with GraXSR [GraS, A6QEW9; GraR, A6QEW8] to form a five-component system required for cationic antimicrobial peptide sensing and resistance (Falord et al., 2012).

Bacteria

VraFG/GraXSR of Staphylococcus aureus 
VraF (A6QEX0)
VraG (A6QEX1)
3.A.1.135:  The Drug Exporter-4 (DrugE4) Family
3.A.1.135.1









The heterodimeric multidrug exporter, YdaG/YbdA [YdaG most closely resembles LmrA (27% I), but YdbA most closely resembles MsbA (3.A.1.106.1) (29% I).] (Both proteins are ABC half transporters; only the heterodimer is active; ethidium, daunomycin and BCECF-AM are substrates; Lubelski et al., 2004) These proteins have been renamed LmrC and LmrD (Lubelski et al., 2006)
Gram-positive bacteria
YdaG/YdbA of Lactococcus lactis YdaG (M-C) (AAK04408)
YdbA (M-C) (AAK04409)
3.A.1.135.2









The heterodimeric putative multidrug exporter, RscA/RscB; probably orthologous to YdaG/YbdA (TC #3.A.1.117.4) [Transcription is activated by stress conditions (heat, acid) and repressed by a 2-component system, CovRS (Dalton et al., 2006)]
Gram-positive bacteria
RscAB of Streptococcus pyogenes RscA (M-C) (568 aas) (Q9A1K5)
RscB (M-C) (594 aas) (Q9A1K4)
3.A.1.136:  The Uncharacterized ABC-3-type (U-ABC3-1) Family
3.A.1.136.1









Putative ABC3 permease complex U-ABC3-1a (403aas; 4TMSs:1+3)
Bacteria
U-ABC3-1a of Treponema denticola (M) (Q73MJ0)
3.A.1.137:  The Uncharacterized ABC-3-type (U-ABC3-2) Family
3.A.1.137.1









Putative ABC-3-type permease complex, ABC3-2a
Archaea
ABC3-2a of Pyrobaculum calidifontis:
ABC3-2a (M) (A3MWP2)
ABC3-2a (C) (A3MWP1)
3.A.1.138:  The Unknown ABC-2-type (ABC2-1) Family
3.A.1.138.1









Unknown ABC-2 transporter complex-1, U-ABC2-TC-1
Archaea
U-ABC2-TC-1 of Picrophilus torridus:
U-ABC2-TC-1a (M) (Q6KYW9)
U-ABC2-TC-1a (C) (Q6KYW8)
3.A.1.139:  The UDP-Glucose Exporter (U-GlcE) Family (UPF0014 Family)
3.A.1.139.1









UDP-glucose exporter, STAR1/STAR2 (sensitive to aluminum rhizotoxicity) (Probable Type I topology) (Huang et al. 2009).

Plants

STAR1/STAR2 of Oryza sativa
STAR1 (C) (Q5Z8H2)
STAR2 (M) (Q5W7C1)
3.A.1.139.2









The YbbM protein (SwissProt family UDF0014; 7 putative TMSs)

Bacteria

YbbM of E. coli (P77307)
3.A.1.139.3









The uncharacterized ABC exporter, U-ABC-M/C

Bacteria

U-ABCC/U-ABC-M of Spirochaeta africana
U-ABC-C (C) (H9UM45)
U-ABC-M (M) (H9UM46)
3.A.1.139.4









Plasma membrane ABC exporter, sensitive to aluminum rhizotoxicity 1/2, STAR1/STAR2 (Larsen et al., 2005). Induced in response to aluminum exposure. 

Plants

STAR1/2 of Arabidopsis thaliana 
STAR1 (C) (Q9C9W0)
STAR2 (M) (Q9ZUT3) 
3.A.1.140:  The FtsX/FtsE Septation (FtsX/FtsE) Family
3.A.1.140.1









The FtsX/FtsE ABC transporter (Arends et al., 2009) (FtsX is of the type III topology). FtsEX directly recruits EnvC to the septum via an interaction between EnvC and a periplasmic loop of FtsX. FtsEX variants predicted to be ATPase defective still recruit EnvC to the septum but fail to promote cell separation. Amidase activation via EnvC in the periplasm is regulated by conformational changes in the FtsEX complex mediated by ATP hydrolysis in the cytoplasm. Since FtsE has been reported to interact with FtsZ, amidase activity may be coupled with the contraction of the FtsZ cytoskeletal ring (Yang et al., 2011).

Bacteria

FtsX/FtsE of E. coli
FtsX (M) (P0AC31)
FtsE (C) (P0A9R7)
3.A.1.141:  The Ethyl Viologen Exporter (EVE) Family (DUF990 Family)
3.A.1.141.1









The ethyl (methyl; benzyl) viologen export pump, EvrABC (EvrB and EvrC of 6 TMSs are members of the large DUF990 superfamily (Prosecka et al., 2009); They appear to be of the ABC-2 topological type).

Bacteria

EvrABC of Synechocystis sp. PCC6803
P73329 slr1910, ABC protein (EvrA)
P74256 slr1174, membrane protein (EvrB)
P74757 slr0610, membrane protein (EvrC)
3.A.1.141.2









ABC transporter of unknown specificity, AbcABC

Bacteria

AbcABC of Thermoanaerobacter tengcongensis
AbcA (M) (Q8R6Q6)
AbcB (M) (Q8R6Q5)
AbcC (C) (Q8R6Q4)
3.A.1.142:  The Glycolipid Flippase (G.L.Flippase) Family
3.A.1.142.1









Glycolipid translocase (flippase) Spr1816/Spr1817 (R.Hakenbeck, personal communication)

Firmicutes

Glycolipid flippase, Spr1816/Spr1817, of Streptococcus pneumoniae
Spr1816 (M) (Q8DNC0)
Spr1817 (C) (Q8DNB9)
3.A.1.143:  The Exoprotein Secretion System (EcsAB(C))
3.A.1.143.1









The exoprotein (including α-amylase) secretion system, EcsAB(C) (Leskelä et al., 1999). Also may play roles in sporulation, competence (Leskelä et al., 1996) and transformation using purified DNA (Takeno et al., 2011). An involvement of EcsC in transport is not established, but it is homologous to the C-terminus of the P-type ATPase, 3.A.3.31.2.

Bacteria

EcsAB(C) of Bacillus subtilis 
EcsA (C) (P55339)
EcsB (M) (P55340)
EcsC (M) (P55341) 
3.A.1.143.2









YthQ (386aas; 8-9 TMSs)/YthP (ATPase; 0 TMSs)

Bacteria

YthPQ (EscAB) of Bacillus amyloliquefaciens
EscA (YthP) (G0IP52)
EscB (YthQ) (G0IP51)
3.A.1.144:  Functionally Uncharacterized ABC2-1 (ABC2-1) Family

 

3.A.1.144.1









Functionally uncharacterized ABC2 transporter #1.  This system is encoded by two genes that overlap and are therefore probably translationally coupled; they are in the same operon with the genes for 2.A.1.144.2.

Archaea

ABC2 transporter #1 of Methanocella arvoryzae 
ABC2-1 (M) (Q0W8T3)
ABC2-1 (C) (Q0W8T4) 
3.A.1.144.2









Functionally uncharacterized ABC2 transporter #2.  This system is encoded by two genes that overlap and are therefore probably translationally coupled; they are in the same operon with the genes for 2.A.1.144.1.

Archaea

ABC2 transporter #2 of Methanocella arvoryzae
ABC2-2 (M) (Q0W8T6)
ABC2-2 (C) (Q0W8T7) 
3.A.1.144.3









Functionally uncharacterized ABC2 transporter #3.

%u03B4-Proteobacteria

ABC2 transporter of Myxococcus xanthus
ABC2-3 (M) (Q1D0V0)
ABC2-3 (C) (Q1D0V1) 
3.A.1.144.4









Functionally uncharacterized ABC2 transporter #4.  The membrane protein is triplicated and of 751aas with 18 putative TMSs.

Chloroflexi

ABC2 transporter of Oscillochloris trichoides 
ABC2 (M) (E1IBA3)
ABC2 (C) (E1IBA4) 
3.A.1.145:  Peptidase Fused Functionally Uncharacterized ABC2-2 (ABC2-2) Family
3.A.1.145.1









ABC2 transporter domain fused to an aminopeptidase N domain (Peptidase M1 family) of 1200 aas with 13 putative N-terminal TMSs.

δ-proteobacteria

ABC2 protein of Myxococcus xanthus
3.A.1.145.2









Putative ABC2 permease of 529 aas and 12 TMSs, Glr0437.

Cyanobacteria

Glr0437 of Gloeobacter violaceus
3.A.1.145.3









ABC2 fusion protein of 1194 aas and 13 putative TMSs.  Annotated as ABC transporter involved in multi-copper enzyme maturation; permease component.

Bacteroidetes

ABC2 protein of Cecembia lonarensis
3.A.1.145.4









Putative ABC2 protein of 537 aas and 14 putative TMSs

Archaea

ABC2 permease of Methanocella paludicola
3.A.1.201:  The Multidrug Resistance Exporter (MDR) Family (ABCB)
3.A.1.201.1









Broad specificity multidrug resistance (MDR1; ABCB1; P-glycoprotein) efflux pump (exports organic cations and amphiphilic compounds of unrelated chemical structure) (These include: anti-biotics, viral agents, cancer agents, hypertensives, depressants, histamines, emetics, and the protease inhibitor, lopinavir. Pgp also exports immunosuppressants, detergents, long-chain fatty acids, HIV protease inhibitors, synthetic tetramethylrosamine analogues, calcein M, etc.); peptide efflux pump; phospholipid (e.g., phosphatidyl serine), cholesterol and sterol flippase (also called ABCB1 and p-gp)). Binds and probably transports inhibitors and agonists of SUR (2.A.1.208.4) (Bessadok et al., 2011). The 3-d structure has been determined (Aller et al., 2009). It can pump from the cytoplasmic leaflet to either the outer leaflet or the outer medium (Katzir et al., 2010). The inhibitor, 5''-fluorosulfonylbenzoyl 5''-adenosine, an ATP analogue, interacts with both drug-substrate- and nucleotide-binding sites (Ohnuma et al., 2011). Inhibited by Sildenafil (Shi et al., 2011) and lapatinib derivatives (Sodani et al., 2012). HG-829 is a potent non-competitive inhibitor (Caceres et al., 2012).  Berberine, palmatine, jateorhizine and coptisine are all P-gp substrates, and cyclosporin A and verapamil are inhibitors (Zhang et al., 2011).  Transports clarithromycin (CAM), a macrolide antibiotic used to treat lung infections, more effectively than azithromycin (AZM) or telithromycin (TEL) (Togami et al. 2012).  Nucleotides, lipids and drugs bind synergistically to the pump (Marcoux et al. 2013).

Animals, fungi, bacteria

MDR1 of Homo sapiens
3.A.1.201.2









Bile salt export pump, BSEP or SPGP (associated with progressive familial intrahepatic cholestasis-2 (also called ABCB11) and benign recurrent intrahepatic cholestasis (Kagawa et al., 2008)). Unconjugaged bile salts and glycine conjugates > taurine conjugates. BSEP mediates biliary excretion of bile acids from hepatocytes. Compounds based on GW4064 (Q96RI1), a representative farnesoid X receptor (RXR) agonist, enhance E297G BSEP transport activity (Misawa et al., 2012).

Animals

BSEP of Homo sapiens
3.A.1.201.3









Short chain fatty acid phosphatidylcholine translocase (phospholipid flippase), MDR3 (associated with progressive familial intrahepatic cholestasis 3 and progressive intrafamilial hepatic disease (Quazi and Molday, 2011)). (Narrow drug specificity relative to MDR1. Exports digoxin, paclitaxel, vinblastin and bile acids.) (also called ABCB4). ABCB4 regulates phosphatidylcholine secretion into bile and its translocation across the plasma membrane in hepatocytes (Voloshyna and Reiss, 2011).

Animals

MDR3 of Homo sapiens
3.A.1.201.4









The multidrug resistance/chloroquine resistance protein, Pfmdr1
Protozoa
Pfmdr1 of Plasmodium falciparum (P13568)
3.A.1.201.5









Auxin efflux pump Pgp1 (MDR1; ABCB1) (Carraro et al. 2012). Regulated by Twd1, an FK506-binding protein immunophilin prolyl/peptidyl isomerase; 8.A.11.1.1 (Bouchard et al., 2006).  Involved in light-dependent hypocotyl elongation (Sidler et al. 1998).

Plants

Pgp1 of Arabidopsis thaliana (Q9ZR72)
3.A.1.201.6









Auxin efflux pump Pgp19 (MDR11) (regulated by Twd1, an FK506-binding protein immunophilin prolyl/peptidyl isomerase; 8.A.11.1.1 (Bouchard et al., 2006))
Plants
Pgp19 of Arabidopsis thaliana (Q9LJX2)
3.A.1.201.7









Auxin efflux pump Pgp4; functions in the basipetal redirection of auxin from the root tip. Strongly expressed in root cap and epidermal cells (Terasaka et al., 2005)
Plants
Pgp4 of Arabidopsis thaliana (MCMC) O80725
3.A.1.201.8









The aluminum chelate (aluminum sensitivity (ALS1)) protein; expressed in root vacuoles half-type ABC transporter (not induced by aluminum; Larsen et al., 2007).
Plants
ALS1 (M-C) of Arabidopsis thaliana (Q0WML0)
3.A.1.201.9









Marine skate liver bile salt exporter, BSEP (1348 aas) (transports taurocholine in an ATP-dependent fashion (Cai et al., 2001)) (Most similar to 3.A.1.201.2)
Animals
BSEP of Raja erinacea (MC MC) (Q90Z35)
3.A.1.201.10









Mdr1; resistance to Cilofungin and other drugs (Lamping et al., 2010)

Fungi

Mdr1 (MCMC) of Aspergillus fumigatus (B0Y3B6)
3.A.1.201.11









Mdr1 azole resistance efflux pump (Lamping et al., 2010)

Fungi

Mdr1 (MCMC) of Cryptococcus (Filobasidiella) neoformans (O43140)
3.A.1.201.12









California mussel ABCB/MDR multixenobiotic resistance efflux pump (Luckenbach and Epel, 2008).

Animals

ABCB/MDR transporter of Mytilus californianus (MCMC) (B2WTH9)
3.A.1.201.13









Plasma membrane AbcB5. Mediates resistance of tumor cells to doxorubicin and other drugs. Catalyzes efflux of rhodamine.

Animals

AbcB5 of Homo sapiens (Q2M3G0)
3.A.1.201.14









P-glycoprotein-1 MDR exporter.  Transports multiple drugs, cancer chemotherapy agents, cancer unrelated compounds and many xenobiotics.  The crystal structure at 3.4 A resolution is available (Jin et al. 2012).  It has 4,000x higher affinity for actinomycin D in the membrane bilayers than in detergent.  A "ball and socket joint" and salt bridges similar to ABC importers suggested that both types of systems, importers and exporters, use the same mechanism to interconnect ATP hydrolysis with transport and achieve alternating access of the substrate binding site to the two sides of the membrane. 

Animals

P-glycoprotein-1 of Caenorhabditis elegans
3.A.1.201.15









MDR efflux pump, ABCB1a.  Exports canonical MDR susbtrates such as calcein-AM, bodipy-verapamil, bodipy-vinblastine and mitoxantrone (Gokirmak et al. 2012).

Animals

ABCB1a of Stronglycentrotus purpuratus
3.A.1.201.16









MDR efflux pump, ABCB4a.  Exports canonical MDR susbtrates such as calcein-AM, bodipy-verapamil, bodipy-vinblastine and mitoxantrone (Gokirmak et al. 2012).

Animals

ABCB4a of Stronglycentrotus purpuratus
3.A.1.201.17









Miltochondrial ABCB10 transporter.  Essential for erythropoiesis, and for protection of mitochondria against oxidative stress.  The 3-d structures of several conformations are available (3ZDQ; Shintre et al. 2013).

Animals

ABCB10 of Homo sapiens
3.A.1.202:  The Cystic Fibrosis Transmembrane Conductance Exporter (CFTR) Family (ABCC)
3.A.1.202.1









Cystic fibrosis transmembrane conductance regulator (CFTR) (also called ABCC7); cyclic AMP-dependent chloride channel; also catalyzes nucleotide (ATP-ADP)-dependent glutathione and glutathione-conjugate flux (Kogan et al., 2003) (may also activate inward rectifying K+ channels). The underlying mechanism by which ATP hydrolysis controls channel opening is described by Gadsby et al., 2006. The most common cause of cystic fibrosis (CF) is defective folding of a cystic fibrosis transmembrane conductance regulator (CFTR) mutant lacking Phe508 (DeltaF508)(Riordan, 2008). The DeltaF508 protein appears to be trapped in a prefolded state with incomplete packing of the transmembrane segments, a defect that can be repaired by direct interaction with correctors such as corr-4a, VRT-325, and VRT-532 (Wang et al., 2007). CFTR interacts directly with MRP4 (3.A.1.208.7) to control Cl- secretion (Li et al., 2007). It has intrinsic adenylate kinase activity that may be of functional importance (Randak and Welsh, 2007). The intact CFTR protein mediates ATPase rather than adenylate kinase activity (Ramjeesingh et al., 2008). Regulated by Na+/H+ exchange regulatory cofactors (NHERF; O14745; TC #8.A.24.1.1) (Seidler et al., 2009). Regulated by protein kinase A and C phosphorylation (Csanády et al., 2010). It is also activated by membrane stretch induced by negative pressures (Zhang et al., 2010). TMS6 plays roles in gating and permeation (Bai et al., 2010; 2011). The 3-D structure revealed the probable location of the channel gate (Rosenberg et al., 2011). Conformational changes opening the CFTR chloride channel pore, coupled to ATP-dependent gating, have been studied (Wang and Linsdell, 2012). Alternating access to the transmembrane domain of CFTR has been demonstrated (Wang and Linsdell, 2012). MRP4 and CFTR function in the regulation of cAMP and beta-adrenergic contraction in cardiac myocytes (Sellers et al., 2012). An asymmetric hourglass, comprising a shallow outward-facing vestibule that tapers toward a narrow "bottleneck" linking the outer vestibule to a large inner cavity extending toward the cytoplasmic extent of the lipid bilayer has been proposed (Norimatsu et al., 2012).

Animals

CFTR of Homo sapiens
3.A.1.203:  The Peroxysomal Fatty Acyl CoA Transporter (P-FAT) Family (ABCD)
3.A.1.203.1









Peroxysomal long chain fatty acyl (LCFA) transporter associated with Zellweger Syndrome
Animals
PMP70 of Homo sapiens
3.A.1.203.2









Peroxysomal long chain fatty acyl (LCFA) Coenzyme A import porter
Yeast
Pat1 (758-870 aas; 5 TMSs)/Pat2 (853 aas; 4 TMSs) of Saccharomyces cerevisiae
3.A.1.203.3









The peroxysomal long chain fatty acid (LCFA) half transporter, ABCD1 (ALD, the adrenoleukodystrophy protein) (functions as a homodimer and accepts acyl-CoA esters (van Roermund et al. 2008)). Transports C24:0 and C26:0 as substrates (van Roermund et al., 2011).  ABCD1 deficiency is associated with plasma and tissue elevation of C24:0 and C26:0 accompanied by demyelination and inflamation (Baarine et al. 2012).

Animals

LCFA transporter of Homo sapiens
3.A.1.203.4









The BacA (Rv1819c) porter (selective for the uptake of bleomycin and antimicrobial peptides) (essential for maintenance of extended chronic infection) (Domenech et al., 2009).

Actinobacteria

BacA of Mycobacterium tuberculosis (M-C) (Q50614)
3.A.1.203.5









Peroxisomal importer, Comatose, of substrates for β-oxidation (transports precursors 2,4-dichlorophenoxybutyric acid (2,4-DB) and indole butyric acid (IBA) (Dietrich et al., 2009). The peroxisomal fatty acyl-CoA transporter, Comatose (CTS ABCD1); (CTS, nBCD1; 1337aas) (Nyathi et al., 2010) determines germination potential and fertility and is essential for acetate metabolism (Linka and Esser 2012).

Plants

Comatose of Arabidopsis thaliana (Q94FB9)
3.A.1.203.6









Peroxisomal long-chain fatty acid importer, PXA1/PXA2 (Lamping et al., 2010; van Roermund et al., 2011)

Yeast

PXA1/PXA2 of Saccharomyces cerevisiae
PXA1 (MC) (P41909)
PXA2 (MC) (P34230)
3.A.1.203.7









Peroxisomal fatty acid transporter, ABCD2 or ALDRP. Transports C22:0 and different unsaturated very long-chain fatty acids including C24:6 and especially C22:6 (van Roermund et al., 2011).

Animals

ABCD2 (M-C) of Homo sapiens (Q9UBJ2)
3.A.1.203.8









Peroxisomal/chloroplast fatty acyl CoA transporter, ABCD2 (Linka and Esser 2012).

Plants

ABCD2 of Arabidopsis thaliana
3.A.1.204:  The Eye Pigment Precursor Transporter (EPP) Family (ABCG)
3.A.1.204.1









Eye pigment precursor transporter
Animals, yeast
White of Drosophila melanogaster
3.A.1.204.2









Drug resistance transporter, ABCG2 (MXR; ABCP) (human breast cancer resistance protein) (Moitra et al., 2011). It exports haem in haempoietic cells (Latunde-Dada et al., 2006) as well as cytotoxic agents (mitoxantrone, flavopiridol, methotrexate, 7-hydroxymethotrexate, methotrexate diglutamate, topotecan, and resveratrol), fluorescent dyes (Hoechst 33342) and other toxic substances (PhIP and pheophorbide a) (Özvegy-Laczka et al., 2005). It also transports folate and sterols: estradiol, and probably cholesterol, progesterone, testosterone and tamoxifen (Janvilisri et al., 2003; Breedveld et al., 2007). It is a homotetramer (Xu et al., 2004). It forms a homodimer bound via a disulfide bond at Cys-603 which stabilizes the protein against ubiquitin-mediated degradation in proteosomes (Wakabayashi et al., 2007). It has 6 established TMSs with the N- and C- termini inside (Wang et al., 2008). Also called breast cancer resistance protein, BCRP (ABCG) (MDR pump) (exports from human breast cancer cell line MCF-7: miloxantrone, daunorubicin, doxorubicin and rhodamine123). Also transports reduced folates as well as mono-, di- and tri-glutamate derivatives of folic acid and methotrexate (Assaraf et al., 2006). It is an active glutathione efflux pump (Brechbuhl et al., 2010). Mutations in ABCG2 cause hyperuricemia and gout , which has led to the identification of urate as a physiological subsrate for ABCG2. Zafirlukast antagonizes ATP-binding cassette subfamily G member 2-mediated multidrug resistance (Sun et al., 2012). Inhibited by Sildenafil (Shi et al., 2011) and lapatinib derivatives (Sodani et al., 2012).

Animals, yeast

ABCG2 (ABCP) of Homo sapiens (Q9UNQ0)
3.A.1.204.3









Putative ABC Transporter WHT-1

Worm
WHT-1 of Caenorhabditis elegans (Q11180)
3.A.1.204.4









The plant cuticular wax exporter, CER5 (in the plasma membrane of epidermal cells; secretes wax to the plant surface) (Pighin et al., 2004)
Plants
CER5 (C-M) of Arabidopsis thaliana (AAU44368)
3.A.1.204.5









The ABCG5 (sterolin-1)/ABCG8 (sterolin-2) heterodimeric neutral sterol (cholesterol and plant sterols) (e.g., sitosterol) (phosphoryl donors ATP > CTP > GTP > UTP) exporter; present in the apical membranes of enterocytes and hepatocytes. Cholesteryl oleate, phosphatidyl choline and enantiomeric cholesterol are poorly transported (mutation of either ABCG5 or ABCG8 cause sitosterolemia and coronary atherosclerosis) (Zhang et al., 2006; Wang et al., 2006; 2011). Involved in cell signalling, creation of membrane asymmetry and apoptosis (Quazi and Molday, 2011).

Animals

ABCG5/ABCG8 of Homo sapiens
ABCG5 (Q9H222)
ABCG8 (Q9H221)
3.A.1.204.6









The efflux porter for phosphatidylcholine and its analogues as well as toxic alkyl phospholipids, ABCG4 (Castanys-Munoz et al., 2007). Also promotes cholesterol efflux to the mature forms of HDL (HDL2 and HDL3) (Voloshyna and Reiss, 2011).

Protozoa

ABCG4 of Leishmania infantum (A4HWI7)
3.A.1.204.7









Multidrug resistance efflux pump, AbcG6, causes camptothecin-resistant parasites (Bosedasgupta et al., 2008)

Euglenozoa

AbcG6 of Leishmania donovani (A8WEV1)
3.A.1.204.8









The epidermal plasma membrane cuticular lipid (wax) exporter, ABCG11 (wbc11); may interact with CER5 (Bird et al., 2007).

Plants

ABCG11 of Arabidopsis thaliana (Q8RXN0)
3.A.1.204.9









The putative multidrug/pigment exporter, Adp1 (Lamping et al., 2010)

Yeast

Adp1 (C-M) of Saccharomyces cerevisiae (P25371)
3.A.1.204.10









AbcH homologue

Animals

AbcH homologue of Caernorhabditis elegans (Q18900)
3.A.1.204.11









AbcG Homologue

Plants

AbcG of Physcomitrella patens (A9SCA8) 
3.A.1.204.12









The intracellular sterol transporter, ABCG1 (Tarling and Edwards, 2011). Involved in cell signalling, creation of membrane asymmetry and apoptosis (Quazi and Molday, 2011). Promotes cholesterol efflux from macrophages to the mature forms of HDL (HDL2 and HDL3) (Voloshyna and Reiss, 2011).  Plays a role in arteriosclerosis (Münch et al. 2012).  The diverse functions invarious cell types have been reviewed by Tarling (2013).  Many mammals have two isoforms, long and short, but mice have only the short isoform (Burns et al. 2013).

Animals

ABCG1 of Homo sapiens (P45844)
3.A.1.204.13









The ABCG1 transporter homologue 

Slime Molds

ABCG1 of Dictyostelium discoideum (Q55DW4)
3.A.1.204.14









ABC transporter-like protein ECU11_1340

Fungi

ECU11_1340 of Encephalitozoon cuniculi
3.A.1.204.15









MDR efflux pump, ABCG2a.  Exports canonical MDR susbtrates such as calcein-AM, bodipy-verapamil, bodipy-vinblastine and mitoxantrone (Gokirmak et al. 2012).

Animals

ABCG2a of Stronglycentrotus purpuratus
3.A.1.204.16









Half ABC transporter, ABCG10.  Secretes isoflavinoids including precursors of the phytoalexin, medicarpin (Banasiak et al. 2013).

Plants

ABCG10 of Medicago truncatula
3.A.1.205:  The Pleiotropic Drug Resistance (PDR) Family (ABCG)
3.A.1.205.1









Pleiotropic drug resistance (PDR) exporter; steroid exporter; sporidesmin toxicity suppressor (Sts1); MDR; cyclic nucleotide exporter; amphipathic anion exporter. Its ATPase activity is inhibited by its substrate, clotrimazole; can use ATP, GTP and maybe UTP to drive efflux (Golin et al., 2007).  Molecular modeling revealed aspects of the binding pocket and mechanism of action (Rutledge et al. 2011).

Yeast

Pdr5 (Sts1; Ydr1) (C-M-C-M) of Saccharomyces cerevisiae (P33302)
3.A.1.205.2









Drug/Sterol/Mutagen exporter, Snq2p
Yeast
Snq2p of Saccharomyces cerevisiae (P32568)
3.A.1.205.3









Weak acid exporter, Pdr12p (exports preservative anions including propionate, sorbate and benzoate) (Mollapour et al., 2008)
Yeast
Pdr12p of Saccharomyces cerevisiae (Q02785)
3.A.1.205.4









Multidrug resistance protein, Cdr1 (confers resistance to cycloheximide and antifungal agents such as azoles and terbinafine) (Holmes et al., 2006; Schuetzer-Muehlbauer et al., 2003); also, transports phospholipids (Shukla et al., 2007). It is the major fluconazole efflux system in fluconazole-resistant C. albicans (Holmes et al., 2008; Basso et al., 2010). Similar to Cdr2. For additional details of both systems, as well as other MDR pumps in various Candida species, see (Cannon et al., 1998). Chimeras between Cdr1 an Cdr2 revealed regions determining substrate specificity (Tanabe et al., 2011).

Yeast

Cdr1 (C-M-C-M) of Candida albicans (P43071)
3.A.1.205.5









Multidrug resistance protein, Cdr2 (confers resistance to azole and other antifungal agents/terbinafine, amorolfine, aspofungin, etc. as well as a variety of metabolic inhibitors) (Schuetzer-Muehlbauer et al., 2003; Basso et al., 2010). Chimeras between Cdr1 an Cdr2 revealed regions determining substrate specificity (Tanabe et al., 2011). Has an external binding site for an inhibiting octapeptide derivative (Niimi et al., 2012).

Yeast

Cdr2 of Candida albicans (P78595)
3.A.1.205.6









Multidrug resistance protein, Cn Afr1 (confers resistance to azole antifungal drugs including fluconazole) (Posteraro et al., 2003)

Fungi

CnAFR1 (C-M-C-M) of Cryptococcus neoformans (Q8X0Z3)
3.A.1.205.7









The multidrug resistance protein, AtrB (confers resistance to all major classes of fungicides as well as natural toxic compounds substrates include: anilinopyrimidine, benzimidazole, phenylpyrrole, phenylpyridylamine, strobirulin, azoles, dicarboximides, quintozene, acriflavin, and rhodamine 6G as well as natural toxins such as camptothecin (an alkaloid) and the stilbene phytoalexin, resveratrol) (Andrade et al., 2000).
Fungi
AtrB of Aspergillus nidulans (P78577)
3.A.1.205.8









The multidrug resistance protein, Pdr11p, mediates sterol uptake by promoting movement of sterols from the plasma membrane to the endoplasmic reticulum where esterification occurs (Li and Prinz, 2004).
Yeast
Pdr11p of Saccharomyces cerevisiae (P40550)
3.A.1.205.9









The plasma membrane Cd2+/Pb2+ efflux pump (heavy metal resistance pump), PDR8, present in root hair and epidermal cells; it may export a broad range of substrates (Kim et al., 2007).  Also reported to transport flavenoid glycosides (phytoalexins) as well as quercitin, kaempeferol and salicylate (Badri et al. 2012).

Plants

PDR8 of Arabidopsis thaliana (Q9XIE2)
3.A.1.205.10









Pleiotropic drug resistance (PDR) exporter, PDR12 (function as a pump to exclude Pb2+ ions and/or Pb2+- containing toxin compounds) (Lee et al., 2005)
Plants
PDR12 of Arabidopsis thaliana (Q9M9E1)
3.A.1.205.11









The brefeldin resistance protein, Bfr1, (also exports actinomycin D, cerulenin, and cytochalasin B) (Turi and Rose, 1995; Nagao et al., 1995).
Yeast
Bfr1 of Schizosaccharomyces pombe (P41820)
3.A.1.205.12









The plasma membrane Pdr10, a negative regulator for incorporation of Pdr12 (TC# 3.A.1.205.3) into detergent-resistant membranes, a novel role for members of the ABC transporter superfamily (Rockwell et al., 2009) (most like 3.A.1.205.1; 67% identity).

Yeast

PDR10 of Saccharomyces cerevisiae (P51533)
3.A.1.205.13









The putative sterol uptake transporter, Aus1 (also protects against antifungal azoles such as fluconazole and itraconazole; (Nakayama et al., 2007).

Yeast

Aus1 of Candida glabrata (Q6FUR1)
3.A.1.205.15









Anaerobically-induced AusI. Specifically stimulated by phosphatidylserine in proteoliposomes. May translocate cholestrol and derivatives (Marek et al., 2011).

Yeast

AusI of Saccharomyces cerevisiae (Q08409)
3.A.1.205.16









ABCG32/PEC1 transporter.  Required for plant cuticle production (Bessire et al. 2011).

Plants

ABCG32/PEC1 of Arabidopsis thaliana
3.A.1.205.17









ABC transporter, PDR1.  Secretes phytohormones such as strigolactones that regulate plant shoot architecture and stimulate germination (Kretzschmar et al. 2012).

Plants

PDR1 of Petunia hybrida
3.A.1.205.18









The monolignol (p-coumaryl alcohol) transporter, ABCG29.  May also transport various phenolic compounds and glucosinolates (Alejandro et al. 2012).  Reported to be required for normal meiotic double strand DNA break formation resulting from interaction with SPO11-1 (De Muyt et al. 2007).

Plants

ABCG29 of Arabidopsis thaliana
3.A.1.205.19









Small molecule transporter, ABCG10.  Poorly expressed in an lrrB mutant (Sugden et al. 2010).

Slime molds

ABCG10 of Dictyostelium discoideum
3.A.1.205.20









TUR2 transporter.  May be a general defense protein. Involved in turion (dormant buds) formation. Confers resistance to the diterpenoid antifungal agent sclareol (van den Brûle et al. 2002).  Induced by abiotic stresses such as cold-stress, cycloheximide and sodium chloride (NaCl). Induction by abscisic acid (ABA) is repressed by cytokinin such as kinetin (Crouzet et al. 2006).

Plants (Aquaphytes)

TUR2 of Spirodela polyrrhiza
3.A.1.205.21









ABC1 transporter.  Excretes secondary metabolites such as terpenes. Involved in both constitutive and jasmonic acid-dependent induced defense. Confers some resistance to sclareol and B.cinerea (Stukkens et al. 2005).  Induced by terpenes such as sclareolide and sclareol, and by some phytohormones such as jasmonic acid (JA) and ethylene. Strongly induced by compatible pathogens such as the fungus B. cinerea, and the bacteria P. syringae pv tabaci, as well as by non pathogenic bacteria such as P. fluorescens, and P. marginalis pv marginalis (Grec et al. 2003).

Plants

ABC1 of Nicotiana plumbaginifolia
3.A.1.206:  The a-Factor Sex Pheromone Exporter (STE) Family (ABCB)
3.A.1.206.1









a-Factor sex pheromone (a hydrophobic isoprenylated (farnesylated) carboxymethylated peptide) exporter, Ste6 (Michaelis and Barrowman 2012).

Yeast

Ste6 of Saccharomyces cerevisiae
3.A.1.207:  The Eukaryotic ABC3 (E-ABC3) Family
(functions unknown; ABC-type ATPases have not been identified.)
3.A.1.207.1









The hypothetical protein, HP (1209aas; 10TMSs:1+6+3; 2-4 are homologous to 8-10; the FtsX domain) (P. tetraurelia has at least 5 paralogues.)
Ciliates
HP of Paramecium tetraurelia (M) (A0ECD9)
3.A.1.207.2









Putative permeases; Duf214 protein (1234aas; 10TMSs: 1+6+3; 2-4 are homologous to 8-10 (the FtsX domain))
Ciliates
Putative permease of Tetrahymena thermophila (M) (Q22NS1)
3.A.1.207.3









Hypothetical protein, HP (1465aas; 8TMSs:1+6+1) (D. discoideum has several paralogues)
Slime mold
HP of Dictyostelium discoideum (M) - Q8ST07
3.A.1.207.4









Hypothetical protein, HP, 1129aas (homologous are found in many unicellular eukaryotes)

Amoeba

HP of Entamoeba histolytica (M) (C4LT38)
3.A.1.208:  The Drug Conjugate Transporter (DCT) Family (ABCC) (Dębska et al., 2011)

Dębska et al., 2011

3.A.1.208.1









Multi-drug resistance-associated protein, MRP1-like protein (MLP1 or MRP1) (Exporter of leukotrienes, glutathione and cysteinyl conjugates of organic anions, drugs, unmodified hydrophobic xenobiotics and hydrophilic conjugated endobiotics). Vincristine and glutathione are co-transported. MRP1 catalyzes export of glutathione during apoptosis (Hammond et al., 2007). Also transports reduced folates as well as mono-, di- and tri-glutamate derivatives of folic acid and methotrexate (Assaraf et al., 2006).
Animals
MRP1 of Rattus norvegicus (O88269)
3.A.1.208.2









Hepatic canalicular conjugate exporter (the Dubin-Johnson Syndrome protein) (transports bilirubin glucuronides; E2 17 β glucuronide, dianionic bile salts such as taurocholate, taurochenodeoxycholate sulfate and taurolithocholate sulfate; reduced glutathione; glutathione conjugates; glucuronides; cysteinyl leukotrienes; arsenic-glutathione complexes and glutathione disulfide; also exports anthracyclines, epipodophyllotosine, Vinca alkaloids, cisplatin, methotrexate, and the protease inhibitor, lopinavir) (also called ABCC2) (Chen and Tiwari, 2011; Krumpochova et al., 2012).  MK-571 is an inhibitor (Zhang et al., 2011).

Animals

cMRP (MRP2; cMOAT) of Homo sapiens (Q92887)
3.A.1.208.3









Oligomycin-resistance protein YOR1 in plasma membrane (confers resistance to oligomycin, rhodamine B, tetracycline, verapamil, eosin Y and ethidium bromide; Grigoras et al., 2007)).

Yeast

YOR1 (M-C-M-C) of Saccharomyces cerevisiae (P53049)
3.A.1.208.4









SUR1 sulfonylurea receptor; subunit and regulator of α-cell ATP-sensitive K+ channel (TC #1.A.2); determines ATP sensitivity; no inherent transport function known; associated with persistent hyperinsulinemic hypoglycemia of infancy due to focal adenomatous hyperplasia (also called ABCC8). Gain-of-function mutations in the genes encoding the ATP-sensitive potassium (K(ATP)) channel subunits Kir6.2 (KCNJ11) and SUR1 (ABCC8) cause neonatal diabetes mellitus. Because mutant channels are inhibited less strongly by MgATP, this increases K(ATP) currents in pancreatic beta cells, thus reducing insulin secretion and producing diabetes (de Wet et al., 2007). Binds ligands (blockers): glibenclamide, tolbutamide, and meglitinide as well as agonists, SR47063 (a cromakalim analog), P1075 (a pinacidil analog), and diazoxide (Bessadok et al., 2011). ATP activates ATP-sensitive potassium channels composed of mutant sulfonylurea receptor 1 and Kir6.2 with diminished PIP2 sensitivity (Pratt and Shyng, 2011). Dominant missense mutations in ABCC9, promoting open channel formation, cause Cantú syndrome (Harakalova et al., 2012; van Bon et al., 2012). The N-terminal transmembrane domain of SUR1 controls gating of Kir6.2 by modulating channel sensitivity to PIP2 (Pratt et al., 2011). Familial mild hyperglycemia is due to the ABCC8-V84I mutation (Gonsorcikova et al., 2011). ATP regulates KATP channels by promoting dimerization and conformational switching (Ortiz et al. 2013).

Animals

SUR1 of Homo sapiens (Q09428)
3.A.1.208.5









Vacuolar multidrug resistance efflux pump, AtMRP2 (catalyzes vacuolar uptake of glutathione conjugates (i.e., 2,4-dinitrophenyl-GS), glucuronide conjugates (i.e., 17 β-estradiol 17(β-D-glucuronide), and reduced glutathione). Also exports the herbicide, 1-chloro-2, 4-dinitrobenzene, and chlorophyll degradation catabolites (Frelet-Barrand et al., 2008).
Plants
AtMRP2 of Arabidopsis thaliana (O64590)
3.A.1.208.6









Metal-thiol conjugate exporter, PgpA; glutathione and trypanothione conjugates are exported; confers arsenite and antimonite resistance (trypanothione is glutathione-spermidine).
Protozoa
PgpA of Leishmania tarentolae (P21441)
3.A.1.208.7









MRP4 (exporter of cyclic nucleotides (cAMP, cGMP)and other nucleotide analogues), purine analogues, methotrexate, bile acids, prostaglandins E1 and E2, reduced folates, 9(2-phosphonylmethyoxyethyl)adenine, leukotrienes, estradiol 17-β-D-glucuronide) and drug sulfate conjugates (inhibited by nonsteroidal antiinflammatory drugs (Reid et al., 2003; Rius et al., 2008)). When overexpressed, it can lower the intracellular concentration of nucleoside/nucleotide analogs, such as the antiviral compounds PMEA (9-(2-phosphonylmethoxyethyl)adenine) or ganciclovir, and of anticancer nucleobase analogs, such as 6-mercaptopurine, after their conversion into the respective nucleotides. MRP4 interacts directly with CFTR (3.A.1.202.1) to control Cl- secretion (Li et al., 2007). Thus, MRP4 is a broad specificity organic anion exporter (Ritter et al., 2005). MRP4 and CFTR function in the regulation of cAMP and beta-adrenergic contraction in cardiac myocytes (Sellers et al., 2012).

Animals

MRP4 (MOAT-B) of Homo sapiens (O15439)
3.A.1.208.8









Drug resistance pump; ABCC1 (MRP1), exports chemotherapeutic agents, organic anions such as leukotriene C4 (LTC4), 17-β-estradiol 17-β-D-glucuronide, glucuronide-X (E217βG, etoposide-glucuronide), estrone-3-sulfate, folic acid and methotrexate, arsenic triglutathione, arsenic and antimonial oxyanians, glutathione (GSH), GSSG, glutathione conjugates (GSH-X; LTC4, DNP-SG, EA-SG, NEH-SG), sulfate-X (E1S, DHEAS), HIV protease inhibitors, anthracyclines, epipodophyllotoxins, and Vinca alkaloids. Changing charged residues in TMS6 (K332, H335 and D336) gave rise to specific changes in specificity (Chen et al., 2006; Haimeur et al., 2002; Leslie et al., 2004). Also exports cobalamine (Vitamin B12) (Beedholm-Ebsen et al., 2010). Also exports cytotoxic metals including antimony, mercuric ions, arsenate and arsenite, but not copper, chromium, cobalt and aluminum, often as glutathione conjugates (Aleo et al., 2005; Vernhet et al., 2000). Notch1 regulates the expression in cultured cancer cells (Cho et al., 2011).  Structural and functional properties of MRP1 have been reviewed comprehensively (He et al. 2011).

Animals

MRP1 of Homo sapiens (P33527)
3.A.1.208.9









Canicular multispecific organic anion transporter, MRP3 (also called ABCC3) (most similar in sequence to MRP2). MRP3 exports epipodophyllotoxins, etoposide and teniposide, estradiol 17-β-D-glucuronide, leukotriene C4, dinitrophenyl S-glutathione, epoposide glucuronide, methotrexate, bilirubin-glucuronides, bile acids, GSH-X (LTC4, DNP-SG) and sulfate-X (taurolithocholate-3-sulfate).  Substrate translocation and stimulated ATP hydrolysis show positive cooperativity (Hill coefficient = 2) and are half-coupled (Seelheim et al. 2012).

Animals

MRP3 of Homo sapiens (O15438)
3.A.1.208.10









Multidrug (anthracycline) resistance organic anion efflux pump (ABC-C6; MRP6; MOAT-E - the pseudoxanthoma elasticum disease protein) exports glutathione conjugates including lencotriene C4, DNP, and N-ethylmaleimide S-glutathione; also exports anthracyclines, epipodophyllotoxins, cisplatin, and probably exports probenecid, benzbromarone and indomethacin (Chen and Tiwari, 2011).

Animals

ABCC6 (MRP6) of Homo sapiens (O95255)
3.A.1.208.11









Vacuolar metal resistance and drug detoxification protein, yeast cadmium factor (YCF1); transports cadmium-glutathione conjugates, glutathione S-conjugated leucotriene C4, organic glutathione S-conjugates, selenodigluthatione, unconjugated bilirubin, reduced glutathione, and diazaborine (Lazard et al., 2011). 

Yeast

YCF1 of Saccharomyces cerevisiae (P39109)
3.A.1.208.12









Bile acid transporter, BAT1 (in vacuoles)
Yeast
BAT1 of Saccharomyces cerevisiae (P32386)
3.A.1.208.13









Cyclic nucleotide (cAMP and cGMP) efflux pump, MRP8 (ABCC11); also exports other nucleoside and nucleotide analogues, and confers resistance to fluoropyrimidines and the anti-AIDS drug, 2',3'-dideoxycytidine (Guo et al., 2003). Human earwax consists of wet and dry types. Dry earwax is frequent in East Asians, whereas wet earwax is common in other populations. A SNP, 538G --> A (rs17822931), in the ABCC11 gene is responsible for determination of earwax type. Cells with allele A show a lower excretory activity for cGMP than those with allele G. The 538G --> A SNP is the first example of DNA polymorphism determining a visible genetic trait (Yoshiura et al., 2006).

Animals

MRP8 (ABCC11) of Homo sapiens (Q9BX80)
3.A.1.208.14









The vacuole (tonoplast) ZmMrp3 anthocyanin pigment transporter (ABCF) (Goodman et al., 2004)
Plants
ZmMrp3 of Zea mays
ZmMrp3 (MC-MC) (Q6J0P5)
3.A.1.208.15









The general organic anion exporter, MRP5 (MOATC). It exports cyclic AMP, cyclic GMP, 5'-FUMP, glutathione and glutathione conjugates and antimonial tartrate). Also transports reduced folates as well as mono-, di- and tri-glutamate derivatives of folic acid and methotrexate (Assaraf et al., 2006). When overexpressed, it can lower the intracellular concentration of nucleoside/nucleotide analogs, such as the antiviral compounds PMEA (9-(2-phosphonylmethoxyethyl)adenine) or ganciclovir, and of anticancer nucleobase analogs, such as 6-mercaptopurine, after their conversion into the respective nucleotides (Ritter et al., 2005).
Animals
MRP5 of Homo sapiens (O15440)
3.A.1.208.16









The vacuolar Abc2p (SPAC3F10.11c) transporter for xenobiotics, glutathione S-conjugates and monochlorobimane (Iwaki et al., 2006)
Yeast
Abc2p of Schizosaccharomyces pombe (MCMC; 1478 aas) (Q10185)
3.A.1.208.17









The vacuolar glutathione-conjugate and chlorophyll catabolite transporter, MRP3 (Tommasini et al., 1998)
Plants
MRP3 of Arabidopsis thaliana (Q9LK64)
3.A.1.208.18









Vacuolar glutathione conjugate, glutathione exporter; mediates cadmium detoxification and ade2 pigmentation in vivo (Sharma et al., 2002). (Most similar to Ycf1 of S. cerevisiae (TC# 3.A.1.208.11; 41% identity))
Plants
Bpt1 of Saccharomyces cerevisiae (P14772)
3.A.1.208.19









The possible HCO3- transporter, HLA3 (Duanmu et al., 2009).

Algae

HLA3 of Chlamydomonas reinhardtii (A8I268)
3.A.1.208.20









The vacuolar MRP1 (sequesters in the vacuole glutathione conjugates, folate mono-glutamates (pteroyl-1-glutamate) and antifolates (methotrexate); (Raichaudhuri et al. 2009) (86% identical to MRP2 (3.A.1.208.5))

Plants

MRP1 of Arabidopsis thaliana (Q9C8G9)
3.A.1.208.21









The thale cress protein ATMRP5 (ATABCC5), a high-affinity inositol hexakisphosphate transporter; involved in guard cell signaling and phytate storage (Nagy et al., 2009).

Plants

MRP5/ABCC5 of Arabidopsis thaliana (Q7GB25)
3.A.1.208.22









California mussel ABCC/MRP-type multixenobiotic resistance efflux pump (Luckenbach and Epel, 2008).

Animals

ABCC/MRP-type exporter of Mytilus californianus (B2WTI0)
3.A.1.208.23









The Sur2B (ABCC9) sulfonylurea receptor. The amino-terminal transmembrane domain of Sur2B binds Kir6.2 (Winkler et al., 2011). Dominant missense mutations in ABCC9, promoting open channel formation, cause Cantú syndrome (Harakalova et al., 2012; van Bon et al., 2012). This protein is part of an ATP-dependent potassium (K(ATP)) channel that couples the metabolic state of a cell with its electrical activity.

Animals

Sur2B of Homo sapiens (O60706)
3.A.1.208.24









Similar to MRP4 of man (TC#3.A.1.208.7). A single amino acid mutation causes resistance to Bt toxin Cry1Ab in the silkworm, Bombyx mori (Atsumi et al., 2012). 83% identical to 3.A.1.208.6.

Insects

MRP4-like ABC transporter of Bombyx mori (G1UHW7)
3.A.1.208.25









The ABC-thiol (cysteine; glutathione) exporter, MrpA (Mukherjee et al., 2007). 83% identical to 3.A.1.208.6.

Kinetoplastid protozoans

MrpA of Leishmania donovani
3.A.1.209:  The MHC Peptide Transporter (TAP) Family (ABCB)
3.A.1.209.1









MHC heterodimeric peptide exporter (TAP) (from cytoplasm to the endoplasmic reticulum) (TAP1=ABCB2; TAP2=ABCB3) (defects in TAP1 or TAP2 cause immunodeficiency) (TAP1/TAP2 is stabilized by tapasin isoforms 1, 2 and 3) (Raghuraman et al., 2002). TAP1 has 10 TMSs, 4 unique N-terminal TMSs and 6 TMSs that form the translocation pore with N- and C-termini in the cytosol (Schrodt et al., 2006). The TAP2 nucleotide binding site appears to be the main catalytic active site driving transport suggesting asymmetry in the transporter (Perria et al., 2006). The TAP complex shows strict coupling between peptide binding and ATP hydrolysis, revealing no basal ATPase activity in the absence of peptides (Herget et al., 2009).

The transporter associated with antigen processing (TAP) plays a key role in the adaptive immune defense against infected or malignantly transformed cells by translocating proteasomal degradation products into the lumen of the endoplasmic reticulum for loading onto MHC class I molecules. TAP transports peptides from 8 to 40 residues, including even branched or modified molecules, suggestive of structural flexibility of the substrate-binding pocket. The bound peptides in side-chains' mobility was strongly restricted at the ends of the peptide, whereas the central region was flexible. Peptides bind to TAP in an extended kinked structure, analogous to those bound to MHC class I proteins (Herget et al., 2011).

Animals, yeast

TAP1/TAP2 of Homo sapiens
3.A.1.209.2









Homodimeric transporter ABCB9 or TAPL. Transports a broad spectrum of peptides (low affinity) from the cytosol to the lysosomal lumen. It exists in two forms (812 aas and 1257 aas). The latter full length protein confers resistance to taxanes and anthracyclines (Kawanobe et al., 2012). Resistance and transport were demonstrated for paclitaxel and docetaxel. Transports a broad range of peptides of 6-60aas (23aas optimal). Has also been detected in the ER. It is stabilized by interaction with LAMP-1 and LAMP-2 (see 9.A.16). (Demirel et al., 2012).

Animals

TAPL or ABCB9 of Homo sapiens (Q9NP78)
3.A.1.210:  The Heavy Metal Transporter (HMT) Family (ABCB)
3.A.1.210.1









The putative mitochondrial iron transporter, ATM1 (possibly specific for iron-sulfur clusters)
Yeast; animals, protozoa bacteria
ATM1 of Saccharomyces cerevisiae
3.A.1.210.2









The vacuolar heavy metal tolerance protein precursor, HMT1 (transports phytochelins and Cd2+·phytochelin complexes) (Prévéral et al., 2009).

Yeast; animals, protozoa bacteria

HMT1 of Schizosaccharomyces pombe
3.A.1.210.3









The ABC transporter homologue
Yeast; animals, protozoa bacteria
ABC transporter homologue in Rickettsia prowazekii
3.A.1.210.4









ABC7 iron transporter (X-linked sideroblastis anemia protein) (also called ABCB7)
Yeast; animals, protozoa bacteria
ABC7 iron transporter of Homo sapiens
3.A.1.210.5









Multidrug resistance homologues, Pfmdr2, protein
Yeast; animals, protozoa bacteria
Pfmdr2 protein of Plasmodium falciparum
3.A.1.210.6









Mitochondrial outer membrane anionic porphyrin uptake half ABC transporter, ABCB6 (expressed in many mammalian tissues including fetal liver) in response to intracellular porphyrin; porphyrin uptake activates de novo porphyrin (haem) biosynthesis (Krishnamurthy et al., 2006).
Animals
ABCB6 of Homo sapiens (Q9NP58; 842 aas)
3.A.1.210.7









The homodimeric heavy metal tolerance protein 1, CeHMT-1 (exports phytochelatin ((γ-Glu-Cys)n)-Cd2 complexes) (Vatamaniuk et al., 2005).  The N-terminal hydrophobic extension domain is required (but not sufficient) for dimerization and therefore is essential for normal function (Kim et al. 2010).

Animals

CeHMT-1 of Caenorhabditis elegans (AAM33380)
3.A.1.210.8









Mitochondrial ABC transporter, ATM3 involved in iron homeostasis. There are three isoforms ATM1, ATM2 and ATM3 (Chen et al., 2007). ATM3 can replace the yeast iron/sulfur cluster exporter better than ATM1 or ATM2. It is most similar to the human and yeast homologues, TC# 3.A.1.210.4 and 3.A.1.210.1, 51% and 47% identical, respectively.
Plants
ATM3 of Arabidopsis thaliana (Q9LVM1)
3.A.1.210.9









The Ni2+/Co2+ exporter AtmA (Mikolay and Nies, 2009).

Bacteria

AmA of Cuperiavidus metallidurans (Q1LRE9).
3.A.1.211:  The Cholesterol/Phospholipid/Retinal (CPR) Flippase Family (ABCA)
3.A.1.211.1









The cholesterol/phospholipid flippase, ABC1 (called ABCA1 in humans; Tangier disease proteins; 2261 aas; sp: O95477). An amphipathic helical region of the N-terminal barrel of the phospholipid transfer protein (PLTP) is critical for ABCA1-dependent cholesterol efflux (Oram et al., 2008). PLTP helix 144-163 removes lipid domains formed by ABCA1, stabilizing ABCA1, interacting with phospholipids, and promoting phospholipid transfer by direct interactions with ABCA1. May transport sphingosine-1-phosphate (Kobayashi et al., 2009). May protect from cardiovascular disease and diabetes (Tang and Oram, 2009). Mediates efflux of cellular cholesterol and phospholipids to apoA-I (Voloshyna and Reiss, 2011).  Hyperglycemia accelerates ABCA1 degradation (Chang et al. 2013).

Animals and plants

ABC1 of Mus musculus
3.A.1.211.2









The retinal-specific ABC transporter (RIM protein, ABCR or ABCA4) (Stargardt's disease protein, involved in retinal/macular degeneration) in the rod outer segment. ABCA4 is an unusual uptake porter that flips N-retinylidene-phosphatidylethanolamine, a product generated from the photobleaching of rhodopsin, from the lumen to the cytoplasmic side of disc membranes following the photobleaching of rhodopsin, insuring that retinoids do not accumulate in disc membranes Molday, 2007; Molday et al. 2009; Tsybovsky et al. 2013). Also transports several vitamin A derivatives (Sun, 2011).   ABCA4 also actively transports phosphatidylethanolamine in the same direction. Mutations known to cause Stargardt disease decrease N-retinylidene-phosphatidylethanolamine and phosphatidylethanolamine transport activity of ABCA4 (Quazi et al. 2012).

Animals

RIM protein (ABCR) of Homo sapiens
3.A.1.211.3









Multidrug resistance pump, ABCA2 (ABC2). Mediates trafficking of LDL-derived free cholesterol (Voloshyna and Reiss, 2011).

Animals

ABCA2 of Homo sapiens
3.A.1.211.4









The aced cell death 7 (ced-7) protein (translocates molecules that mediate adhesion between dying and engulfing embryonic cells during programmed death).
Animals
Ced-7 of Caenorhabditis elegans (P34358)
3.A.1.211.5









The surfactant-secreting porter, ABCA3 (exports lipids and proteins into lamellar bodies). Fatal surfactant deficiency (FSD) can result from mutations in ABCA3, causing abnormal intracellular localization (type I) or decreased ATP hydrolysis (type II). ABCA3 is found in lamellar bodies of lung alveolar type II cells where it probably secretes surfactants (mixture of lipids; e.g., PC) and proteins (e.g., surfactant proteins A, B, C and D) stored in lamellar bodies and exocytosed (Matsumura et al., 2006). ABCA3 plays an essential role in pulmonary surfactant lipid metabolism and lamellar body biogenesis, probably by transporting these lipids as substrates (Ban et al., 2007). Cheong et al., 2007 have shown that ABCA3 is critical for lamellar body biogenesis in mice. They suggest it functions in surfactant-protein B processing and lung development late in gestation. Lymphoma exosomes shield target cells from antibody attack, and exosome biogenesis is modulated by lysosome-associated ABCA3 which mediates resistance to chemotherapy. Silencing ABCA3 enhances susceptability of target cells to antibody-mediated lysis. Mechanisms of cancer cell resistance to drugs and antibodies are linked in an ABCA3-dependent pathway of exosome secretion (Aung et al., 2011).

Animals

ABCA3 of Homo sapiens (Q99758)
3.A.1.211.6









Xenobiotic transporter, ABCA8 (transports estradiol-β-glucuronide, taurocholate, LTC4, para-amino-hippurate and ochratoxin-A (Tsuruoka et al., 2002)
Animals
ABCA8 of Homo sapiens (O94911)
3.A.1.211.7









Half sized ABCA exporter, AbcA
Amoeba
AbcA of Dictyostelium discoideum
M-C 655 aas; (Q94479)
3.A.1.211.8









AbcA12 Keratinocyte lipid transporter.  Transports lipids in lamellar granules to the apical surface of granular layer keratinocytes. Extracellular lipids, including ceramide, are thought to be essential for skin barrier function. ABCA12 mutations underlie the three main types of autosomal recessive congenital ichthyoses: harlequin ichthyosis, lamellar ichthyosis and congenital ichthyosiform erythroderma. ABCA12 mutations lead to defective lipid transport via lamellar granules in the keratinocytes, resulting in malformation of the epidermal lipid barrier and ichthyosis phenotypes. Lipid transport by ABCA12 is indispensable for intact differentiation of keratinocytes (Akiyama, 2011). 

Animals

AbcA12 of Mus musculus (B9EKF0)
3.A.1.211.9









ABCA5. Mediates cholesterol efflux to HDL3 (Voloshyna and Reiss, 2011).

Animals

ABCA5 of Homo sapiens (Q8WWZ7)
3.A.1.211.10









ABCA7. Regulates cellular efflux of phospholipids but not cholesterol, to apo A-1 (Voloshyna and Reiss, 2011).

Animals

ABCA7 of Homo sapiens (Q8IZY2)
3.A.1.211.11









AOH1; ABCA1 transporter.  Substrates unknown.

Plants

ABCA1 of Arabidopsis thaliana
3.A.1.212:  The Mitochondrial Peptide Exporter (MPE) Family (ABCB)
3.A.1.212.1









The mitochondrial peptide exporter, Mdl1p (exports peptides of 6-21 amino acyl residues from the mitochondrial matrix as well as degradation products of misassembled respiratory chain complexes) (Janas et al., 2003; van der Does et al., 2006; Gompf et al., 2007). A leaderless Mdl1p targets to the ER membrane instead of to the mitochondria (Gompf et al., 2007).
Yeast
Mdl1p of Saccharomyces cerevisiae (P33310)
3.A.1.212.2









ABC mitochondrial peptide/MDR half transporter, MdlB. High copy number suppressor of ATM1 [iron-sulfur cluster transporter (3.A.1.210.1)]
Bacteria
Md1B of Saccharomyces cerevisiae (M-C) (P33311)