4.A.1 The PTS Glucose-Glucoside (Glc) Family

The Glc family includes porters specific for glucose, glucosamine, N-acetylglucosamine and a large variety of α- and β-glucosides. However, not all β-glucoside PTS porters are in this class, as the PTS porter first described as the cellobiose (Cel) β-glucoside porter is the diacetylchitobiose porter in the Lac family (TC #4.A.3). The IIA, IIB and IIC domains of all of the group translocators listed below are demonstrably homologous. These porters (the IIC domains) show limited sequence similarity with and are homologous to members of the Fru family (TC #4.A.2) and with (but less so) with members of the Lac family (TC #4.A.3). The IIC domains of the glucose (4.A.1.1) and glucoside (4.A.1.2) subfamilies are nearly as distant from each other as they are from the Fru, Mtl and Lac families. As is true of other members of the PTS-GFL superfamily, the IIC domains of these permeases probably have a uniform 10 TMS topology (McCoy et al. 2016; Vastermark and Saier 2016).  Butanol toxicity in Clostridium acetobutylicum results in destruction of the PTS, thereby preventing glucose transport and phosphorylation (Gao et al. 2021).

Several of the PTS porters in the Glc family lack their own IIA domains and instead use the glucose IIA protein (IIAglc or Crr). Most of these porters have the B and C domains linked together in a single polypeptide chain. A cysteyl residue in the IIB domain is phosphorylated by direct phosphoryl transfer from IIAglc(his~P) or one of its homologues. Those porters which lack a IIA domain include the maltose (Mal), arbutin-salicin-cellobiose (ASC), trehalose (Tre), putative glucoside (Glv) and sucrose (Scr) porters of E. coli. Most, but not all Scr porters of other bacteria also lack a IIA domain.

BglF consists of a transmembrane domain, which in addition to TMSs, contains a large cytoplasmic loop. According to Yagur-Kroll et al., 2009, this loop, connecting TMSI to TMSII, contains regions that alternate between facing-in and facing-out states and creates the sugar translocation channel. Yagur-Kroll et al., 2009 demonstrated spatial proximity between positions at the center of the big loop and the phosphorylation site, suggesting that the two regions come together to execute sugar phosphotransfer.

The three-dimensional structures of the IIA and IIB domains of the E. coli glucose porter have been elucidated. IIAglc has a complex β-sandwich structure while IIBglc is a split αβ-sandwich with a topology unrelated to the split αβ-sandwich structure of HPr.  Some bacteria have many PTS transport systems belonging to different families.  For example, the solventogenic Clostridium acetobutylicum ATCC 824 has 13 altogether with 6 in the Glc family, 2 in the Fru family, 2 in the Lac family, 1 in the Gat family and 2 in the Man family.  However, Clostridium beijerinckii has 43 phosphotransferases (Mitchell 2015).

This family belongs to the PTS-GFL Superfamily.



Carmona, S.B., F. Moreno, F. Bolívar, G. Gosset, and A. Escalante. (2015). Inactivation of the PTS as a Strategy to Engineer the Production of Aromatic Metabolites in Escherichia coli. J. Mol. Microbiol. Biotechnol. 25: 195-208.

Chen, C., G. Zhao, W. Chen, and B. Guo. (2015). Metabolism of Fructooligosaccharides in Lactobacillus plantarum ST-III via Differential Gene Transcription and Alteration of Cell Membrane Fluidity. Appl. Environ. Microbiol. 81: 7697-7707.

Chen, Y., J. Reizer, M.H. Saier, Jr, W.J. Fairbrother, and P.E. Wright. (1993). Mapping of the binding interfaces of the proteins of the bacterial phosphotransferase system, HPr and IIAglc. Biochemistry 32: 32-37.

Christiansen, I. and W. Hengstenberg. (1999). Staphylococcal phosphoenolpyruvate-dependent phosphotransferase system--two highly similar glucose permeases in Staphylococcus carnosus with different glucoside specificity: protein engineering in vivo? Microbiology 145(Pt10): 2881-2889.

Cote, C.K. and A.L. Honeyman. (2003). The LicT protein acts as both a positive and a negative regulator of loci within the bgl regulon of Streptooccus mutans. Microbiology 149: 1333-1340.

Cote, C.K., D. Cvitkovitch, A.S. Bleiweis, and A.L. Honeyman. (2000). A novel β-glucoside-specific PTS locus from Streptococcus mutans that is not inhibited by glucose. Microbiology 146: 1555-1563.

Dahl, U., T. Jaeger, B.T. Nguyen, J.M. Sattler, and C. Mayer. (2004). Identification of a phosphotransferase system of Escherichia coli required for growth on N-acetylmuramic acid. J. Bacteriol. 186: 2385-2392.

Decker, K., F. Gerhardt, and W. Boos. (1999). The role of the trehalose system in regulating the maltose regulon of Escherichia coli. Mol. Microbiol. 32: 777-788.

Desai, S.K., K. Nandimath, and S. Mahadevan. (2010). Diverse pathways for salicin utilization in Shigella sonnei and Escherichia coli carrying an impaired bgl operon. Arch. Microbiol. 192: 821-833.

Eberstadt, M., S.G. Grdadolnik, G. Gemmecker, H. Kessler, A. Buhr, and B. Erni. (1996). Solution structure of the IIB domain of the glucose transporter of Escherichia coli. Biochemistry 35: 11286-11292.

Ells, T.C. and L. Truelstrup Hansen. (2011). Increased thermal and osmotic stress resistance in Listeria monocytogenes 568 grown in the presence of trehalose due to inactivation of the phosphotrehalase-encoding gene treA. Appl. Environ. Microbiol. 77: 6841-6851.

Engels, V., and V.F. Wendisch. (2007). The DeoR-type regulator SugR represses expression of ptsG in Corynebacterium glutamicum. J. Bacteriol. 189: 2955-2966.

Francl, A.L., T. Thongaram, and M.J. Miller. (2010). The PTS transporters of Lactobacillus gasseri ATCC 33323. BMC Microbiol 10: 77.

Gao, Y., X. Zhou, M.M. Zhang, Y.J. Liu, X.P. Guo, C.R. Lei, W.J. Li, and D. Lu. (2021). Response characteristics of the membrane integrity and physiological activities of the mutant strain Y217 under exogenous butanol stress. Appl. Microbiol. Biotechnol. 105: 2455-2472.

Gordon, N., R. Rosenblum, A. Nussbaum-Shochat, E. Eliahoo, and O. Amster-Choder. (2015). A Search for Ribonucleic Antiterminator Sites in Bacterial Genomes: Not Only Antitermination? J. Mol. Microbiol. Biotechnol. 25: 143-153.

Hurley, J.H., H.R. Faber, D. Worthylake, N.D. Meadow, S. Roseman, D.W. Pettigrew, and S.J. Remington. (1993). Structure of the regulatory complex of Escherichia coli IIIGlc with glycerol kinase. Science 259: 673-677.

Jeckelmann, J.M. and B. Erni. (2020). Transporters of glucose and other carbohydrates in bacteria. Pflugers Arch. [Epub: Ahead of Print]

Johnson, D.A., S.G. Tetu, K. Phillippy, J. Chen, Q. Ren, and I.T. Paulsen. (2008). High-throughput phenotypic characterization of Pseudomonas aeruginosa membrane transport genes. PLoS Genet 4: e1000211.

Joyet, P., H. Bouraoui, F.M. Aké, M. Derkaoui, A.C. Zébré, T.N. Cao, M. Ventroux, S. Nessler, M.F. Noirot-Gros, J. Deutscher, and E. Milohanic. (2013). Transcription regulators controlled by interaction with enzyme IIB components of the phosphoenolpyruvate: sugar phosphotransferase system. Biochim. Biophys. Acta. 1834: 1415-1424.

Kalbermatter, D., P.L. Chiu, J.M. Jeckelmann, Z. Ucurum, T. Walz, and D. Fotiadis. (2017). Electron crystallography reveals that substrate release from the PTS IIC glucose transporter is coupled to a subtle conformational change. J Struct Biol. [Epub: Ahead of Print]

Kawamoto, H., T. Morita, A. Shimizu, T. Inada, and H. Aiba. (2005). Implication of membrane localization of target mRNA in the action of a small RNA: mechanism of post-transcriptional regulation of glucose transporter in Escherichia coli. Genes Dev. 19: 328-338.

Khajanchi, B.K., E. Odeh, L. Gao, M.B. Jacobs, M.T. Philipp, T. Lin, and S.J. Norris. (2016). Phosphoenolpyruvate Phosphotransferase System Components Modulate Gene Transcription and Virulence of Borrelia burgdorferi. Infect. Immun. 84: 754-764.

Kotrba, P., M. Inui, and H. Yukawa. (2003). A single V317A or V317M substitution in Enzyme II of a newly identified β-glucoside phosphotransferase and utilization system of Corynebacterium glutamicum R extends its specificity towards cellobiose. Microbiology 149: 1569-1580.

Liao, D.I., G. Kapadia, P. Reddy, M.H. Saier, Jr., J. Reizer, and O. Herzberg. (1991). The structure of the IIA domain of the glucose permease of Bacillus subtilisat a 2.2-Å resolution. Biochemistry 30: 9583-9594.

Lloyd, C.R., S. Park, J. Fei, and C.K. Vanderpool. (2017). The Small Protein SgrT Controls Transport Activity of the Glucose-Specific Phosphotransferase System. J. Bacteriol. 199:.

Mazé, A., M. O''Connell-Motherway, G.F. Fitzgerald, J. Deutscher, and D. van Sinderen. (2007). Identification and characterization of a fructose phosphotransferase system in Bifidobacterium breve UCC2003. Appl. Environ. Microbiol. 73: 545-553.

McCoy, J.G., Z. Ren, V. Stanevich, J. Lee, S. Mitra, E.J. Levin, S. Poget, M. Quick, W. Im, and M. Zhou. (2016). The Structure of a Sugar Transporter of the Glucose EIIC Superfamily Provides Insight into the Elevator Mechanism of Membrane Transport. Structure 24: 956-964.

Mitchell, W.J. (2015). The Phosphotransferase System in Solventogenic Clostridia. J. Mol. Microbiol. Biotechnol. 25: 129-142.

Morabbi Heravi, K. and J. Altenbuchner. (2018). Cross Talk among Transporters of the Phosphoenolpyruvate-Dependent Phosphotransferase System in Bacillus subtilis. J. Bacteriol. 200:.

Nguyen, T.X., M.R. Yen, R.D. Barabote, and M.H. Saier, Jr. (2006). Topological predictions for integral membrane permeases of the phosphoenolpyruvate:sugar phosphotransferase system. J. Mol. Microbiol. Biotechnol. 11: 345-360.

Nothaft, H., S. Rigali, B. Boomsma, M. Swiatek, K.J. McDowall, G.P. van Wezel, and F. Titgemeyer. (2010). The permease gene nagE2 is the key to N-acetylglucosamine sensing and utilization in Streptomyces coelicolor and is subject to multi-level control. Mol. Microbiol. 75: 1133-1144.

Pickering, B.S., J.E. Lopilato, D.R. Smith, and P.I. Watnick. (2014). The transcription factor Mlc promotes Vibrio cholerae biofilm formation through repression of phosphotransferase system components. J. Bacteriol. 196: 2423-2430.

Pikis, A., S. Hess, I. Arnold, B. Erni, and J. Thompson. (2006). Genetic requirements for growth of Escherichia coli K12 on methyl-α-D-glucopyranoside and the five α-D-glucosyl-D-fructose isomers of sucrose. J. Biol. Chem. 281: 17900-17908.

Pikis, A., S. Immel, S.A. Robrish, and J. Thompson. (2002). Metabolism of sucrose and its five isomers by Fusobacterium mortiferum. Microbiology 148: 843-852.

Plumbridge, J. (2002). Regulation of gene expression in the PTS in Escherichia coli: the role and interactions of Mlc. Curr. Opin. Microbiol. 5: 187-193.

Plumbridge, J. (2015). Regulation of the Utilization of Amino Sugars by Escherichia coli and Bacillus subtilis : Same Genes, Different Control. J. Mol. Microbiol. Biotechnol. 25: 154-167.

Postma, P.W., J.W. Lengeler, and G.R. Jacobson. (1996). Phosphoenolpyruvate:carbohydrate phosphotransferase systems. In: F.C. Neidhardt (ed.), Escherichia coli and Salmonella: Cellular and Molecular Biology, Vol. 1, 2nd ed. Washington, DC: ASM Press, pp. 1149-1174.

Reidl, J. and W. Boos. (1991). The malX malY operon of Escherichia coli encodes a novel enzyme II of the phosphotransferase system recognizing glucose and maltose and an enzyme abolishing the endogenous induction of the maltose system. J. Bacteriol. 173: 4862-4876.

Reizer, J., I.T. Paulsen, A. Reizer, F. Titgemeyer, and M.H. Saier, Jr. (1996). Novel phosphotransferase system genes revealed by bacterial genome analysis: the complete complement of pts genes in Mycoplasma genitalium. Microbial Comp. Genomics 1: 151-164.

Reizer, J., S. Bachem, A. Reizer, M. Arnaud, M.H. Saier, Jr., and J. Stülke. (1999). Novel phosphotransferase system genes revealed by genome analysis – the complete complement of PTS proteins encoded within the genome of Bacillus subtilis Microbiology 145: 3419-3429.

Reizer, J., V. Michotey, A. Reizer, and M.H. Saier, Jr. (1994). Novel phototransferase system genes revealed by bacterial genome analysis: unique, putative fructose- and glucoside-specific systems. Prot. Sci. 3: 440-450.

Robillard, G.T. and J. Broos. (1999). Structure/function studies on the bacterial carbohydrate transporters, enzymes II, of the phosphoenolpyruvate-dependent phosphotransferase system. Biochim. Biophys. Acta 1422: 73-104.

Saito, A. and H. Schrempf. (2004). Mutational analysis of the binding affinity and transport activity for N-acetylglucosamine of the novel ABC transporter Ngc in the chitin-degrader Streptomyces olivaceoviridis. Mol. Genet. Genomics 271: 545-553.

Schöck, F. and M.K. Dahl. (1996). Analysis of DNA flanking the treA gene of Bacillus subtilis reveals genes encoding a putative specific enzyme IITre and a potential regulator of the trehalose operon. Gene 175: 59-63.

Shelburne, S.A., 3rd, D.B. Keith, M.T. Davenport, N. Horstmann, R.G. Brennan, and J.M. Musser. (2008). Molecular characterization of group A Streptococcus maltodextrin catabolism and its role in pharyngitis. Mol. Microbiol. 69: 436-452.

Steen, J.A., N. Bohlke, C.E. Vickers, and L.K. Nielsen. (2014). The trehalose phosphotransferase system (PTS) in E. coli W can transport low levels of sucrose that are sufficient to facilitate induction of the csc sucrose catabolism operon. PLoS One 9: e88688.

Thompson, J. and A. Pikis. (2012). Metabolism of sugars by genetically diverse species of oral Leptotrichia. Mol Oral Microbiol 27: 34-44.

Tortosa, P. and D. Le Coq. (1995). A ribonucleic antiterminator sequence (RAT) and a distant palindrome are both involved in sucrose induction of the Bacillus subtilis sacXY regulatory operon. Microbiology 141(Pt11): 2921-2927.

Ujiie, H., T. Matsutani, H. Tomatsu, A. Fujihara, C. Ushida, Y. Miwa, Y. Fujita, H. Himeno, and A. Muto. (2009). Trans-translation is involved in the CcpA-dependent tagging and degradation of TreP in Bacillus subtilis. J Biochem 145: 59-66.

Vargas-Tah, A., L.M. Martínez, G. Hernández-Chávez, M. Rocha, A. Martínez, F. Bolívar, and G. Gosset. (2015). Production of cinnamic and p-hydroxycinnamic acid from sugar mixtures with engineered Escherichia coli. Microb Cell Fact 14: 6.

Vastermark, A. and M.H. Saier, Jr. (2016). Time to Stop Holding the Elevator: A New Piece of the Transport Protein Mechanism Puzzle. Structure 24: 845-846.

Wang, F., X. Xiao, A. Saito, and H. Schrempf. (2002). Streptomyces olivaceoviridis possesses a phosphotransferase system that mediates specific, phosphoenolpyruvate-dependent uptake of N-acetylglucosamine. Mol. Genet. Genomics 268: 344-351.

Webb, A.J., K.A. Homer, and A.H. Hosie. (2007). A phosphoenolpyruvate-dependent phosphotransferase system is the principal maltose transporter in Streptococcus mutans. J. Bacteriol. 189: 3322-3327.

Yagur-Kroll, S., A. Ido, and O. Amster-Choder. (2009). Spatial arrangement of the β-glucoside transporter from Escherichia coli. J. Bacteriol. 191: 3086-3094.

Yamamoto, H., M. Serizawa, J. Thompson, and J. Sekiguchi. (2001). Regulation of the glv operon in Bacillus subtilis: YfiA (GlvR) is a positive regulator of the operon that is repressed through CcpA and cre. J. Bacteriol. 183: 5110-5121.

Zurbriggen, A., P. Schneider, P. Bähler, U. Baumann, and B. Erni. (2010). Expression, purification, crystallization and preliminary X-ray analysis of the EIICGlc domain of the Escherichia coli glucose transporter. Acta Crystallogr Sect F Struct Biol Cryst Commun 66: 684-688.


TC#NameOrganismal TypeExample

Glucose porter (PtsG; GlcA; Umg) (transports D-glucose and α-methyl-D-glucopyranoside).  The IIC domain has been crystallized, and x-ray data to 4.5 Å resolution have been described (Zurbriggen et al. 2010).  The system has been manipulated to engineer increased production of aromatic metabolites (Carmona et al. 2015, Vargas-Tah et al. 2015). The presence or absence of D-glucose reflects the transporter before and after release of the transported glucose into the cytoplasm. The transition associated with substrate release appears to require a subtle structural rearrangement in the region that includes hairpin 1 (Kalbermatter et al. 2017).  Mlc (for makes large colonies) represses transcription of the genes encoding enzyme I, HPr, EIIBCGlc and EIIABCDMan in defined media that lack PTS substrates. When glucose is present, the unphosphorylated form of EIIBCGlc sequesters Mlc to the cell membrane, preventing its interaction with DNA (Plumbridge 2002, Joyet et al. 2013). The Vibrio Mlc functions similarly (Pickering et al. 2014). A small (43 aa) protein, SgrT, acts in tandem with a well-characterized small RNA during metabolic stress, due to the accumulation of cytoplasmic sugar-Ps to help bacterial cells maintain balanced metabolism and continue growing. SgrT acts on the glucose transport system, inhibiting its activity under stress conditions in order to allow cells to utilize alternative carbon sources (Lloyd et al. 2017). ptsG mRNA localization to the inner membrane, coupled with the membrane insertion of nascent peptide, mediates Hfq/SgrS-dependent ptsG mRNA destabilization, presumably by reducing second rounds of translation (Kawamoto et al. 2005). SgrT is a small protein of 43 aas that allosterically inhibits IICBGlc. while SgrS is a small RNA coompementary to ptsG mRNA that influences its expression.  The sgrST operon is regulated by SgrR, a glucose-6-P-dependent transcriptional activator (Jeckelmann and Erni 2020).


Bacteria, proteobacteria

PtsG/Crr; Glucose IICB/IIA complex of E. coli

4.A.1.1.10The α-glucoside-specific IICB, AglB (transports glucose, methyl-α-glucoside, maltitol, isomaltose, trehalulose α(1→1), turanose α(1→3), maltulose α(1→4), leucrose α(1→5), and palatinose α(1→6), but not sucrose (most resembles 4.A.1.1.4 and 4.A.1.1.8) (Pikis et al., 2006)BacteriaGlucose/α-glucoside IICB complex of Klebsiella pneumoniae (Q9AGA7)
4.A.1.1.11The maltose/maltotriose porter, MalT (31% identical to 4.A.1.1.9) (Webb et al., 2007)BacteriaMalT IICBA of Streptococcus mutans (Q8DS05)
4.A.1.1.12Maltose/Maltotriose PTS transporter, MalT (Shelburne et al., 2008) 631aas (68% identical to 4.A.1.1.11 from S. mutansBacteriaMalT IICBA of Streptococcus pyogenes (Q48WG5)

Glucose porter, GlcA (IICBA). Glucose uptake is inhibited by 2-deoxyglucose and methyl-β-D-glucoside (Christiansen and Hengstenberg, 1999).


GlcA of Staphylococcus carnosus (Q57071)


Glucose porter GlcB (IICBA). Glucose uptake is inhibited by methyl-α-D-glucoside, methyl-β-D-glucoside, p-nitrophenyl-α-D-glucoside, o-nitrophenyl-β-D-glucoside and salicin, but not by 2-deoxyglucose. Mannose and N-acetylglucosamine are not transported (Christiansen and Hengstenberg, 1999).


GlcB of Staphylococcus carnosus (Q53922)


N-acetyl glucosamine-specific PTS permease, GlcNAc IIBC/GlcNAc I-HPr-IIA (Johnson et al. 2008)


GlcNAc IIBC/GlcNAc I-HPr-IIA of Pseudomonas aeruginosa


PTS uptake porter for sucrose isomers, IICB (Thompson and Pikis 2012).


IICB for sucose isomers of Leptotrichia buccalis


The Maltose group translocator, MalT of 470 aas and 10 TMSs. Takes up extracellular maltose, releasing maltose-phosphate into the cytoplasm.  The 3-d structure at 2.55 Å resolution has been solved (McCoy et al. 2016; Vastermark and Saier 2016).

MalT of Bacillus cereus


Glucose-specific Enzyme IIBC of the PTS, PtsG.  Essential for infectivity and virulence in mice although no other PTS Enzyme II is required (Khajanchi et al. 2016).

IIBCGlc (PtsG) of Borrelia burgdorferi


PTS α-glucoside transporter, subunit IICB (Francl et al. 2010).

IICB of Lactobacillus gasseri


N-Acetyl glucosamine (NAG) porter (NagE) (Plumbridge 2015).


NagE, the IICBANag complex of E. coli


The N-acetylglucosamine PTS transporter/kinase, NagE2 (416 aas; IIC)/NagF (77 aas; IIB).  The IIA specific for glucose (Crr) is the IIA for this system, and activity depends on Enzyme I and HPr (Nothaft et al. 2010). The genes encoding these enzymes are regulated by two transcription factors, DasR and AtrA, and the system serves as a sensor as well as a transporter/kinase (Nothaft et al. 2010).

NagE2F of Streptomyces coelicolor


Enzyme IIA of 168 aas.  It is of the glucose type and can phosphorylate maltose via MalP (TC# 4.A..1.1.8), N-acetyl glucosamine via NagP (TC#4.A.1.1.7), sucrose via SacX (TC#4.A.1.2.10) and SacP (TC# 4.A.1.2.9), and trehalose via TreP (TC# 4.A.1.2.8), none of which have their own IIA protein (Morabbi Heravi and Altenbuchner 2018). Other Enzymes IIA could also phosphorlyate these sugars via their respective IIBC proteins.

PtsA (YpqE) IIA protein of Bacillus subtilis


Maltose/glucose porter (MalX) of 510 aas and 10 TMSs.  This system functions with the glucose IIA protein (Reidl and Boos 1991; Jeckelmann and Erni 2020).


Maltose IICB complex (MalX) of E. coli

4.A.1.1.4The α-glucoside-specific IICB (MalB) (substrates probably include glucosyl-α-fructose disaccharides: trehalurose (α-1,1), turanose (α-1,3), malturose (α-1,4), leucrose (α-1,5) and palatinose (α-1,6)).BacteriaThe α-glucoside IICB, MalB of Fusobacterium mortiferum

N-Acetylglucosamine (NAG) porter (PtsBC1C2)(also may facilitate xylose transport) (Saito and Schrempf 2004).


The NAG IICC'B complex of Streptomyces olivaceoviridis (IIA not identified)
IICNag (PtsC1)
IIC'Nag (PtsC2)
IIBNag (PtsB)


The glucosamine IICBA porter (GamP) (40% identical to 4.A.1.1.2) (Plumbridge 2015). The IIA domain in this protein can transfer the phosphoryl moiety to the maltose, N-acetylglucosamine, sucrose and trehalose PTS systems (MalP, NagP, SacP and TreP, respectively) (Morabbi Heravi and Altenbuchner 2018).

Bacteria; firmicute

GamP of Bacillus subtilis (gi2632521)


The N-acetylglucosamine IICB porter (NagP; YflF) (45% identical to 4.A.1.1.2) (Plumbridge 2015).

Bacteria; firmicute

NagP of Bacillus subtilis (gi2443228)


The maltose IICB porter (MalP; GlvC) (56% identical to 4.A.1.1.4) (Yamamoto et al., 2001).


MalP of Bacillus subtilis (IICBA) (P54715)

4.A.1.1.9The glucose IICBA porter (PtsG) 44% identical to 4.A.1.1.1)BacteriaPtsG of Bacillus subtilis (P20166)

TC#NameOrganismal TypeExample
4.A.1.2.1Sucrose porter (ScrA) BacteriaSucrose IIBC complex (ScrA) of plasmid pUR400 from Salmonella typhimurium

Sucrose porter and regulatory sensor, IIBC (SacX) (43% identical to 4.A.1.2.1) (Tortosa and Le Coq 1995). The IIA domains of PtsA, GamP, PtsG and GmuA can all phosphorylate the IIB domain in the SacX sensor (Morabbi Heravi and Altenbuchner 2018).


SacX of Bacillus subtilis (P15400)

4.A.1.2.11Aryl β-glucoside porter, IIBCA (BglP; SytA) (35% identical to 4.A.1.2.2)BacteriaBglP of Bacillus subtilis (P40739)
4.A.1.2.12The sucrose porter, PtsS (regulated by SugR which also regulates other enzymes II) (Engels and Wendisch, 2007)BacteriaPtsS (IIBCA) complex of Corynebacterium glutamicum (Q8NMD6)

Trehalose PTS permease IIBC of 494 aas (Ells and Truelstrup Hansen 2011).


Trehalose IIBC of Listeria monocytogenese


PTS beta-glucoside transporter, EIIBCA of 672 aas and 12 predicted TMSs (Francl et al. 2010).

EIIBCA of Lactobacillus gasseri


PTS beta-glucoside transporter, EIIBCA of 624 aas and 10 predicted TMSs (Francl et al. 2010).

EIIBCA of Lactobacillus gasseri


PTS beta-glucoside transporter, EIIBCA of 647 aas and 10 predicted TMSs (Francl et al. 2010).

EIIBCA of Lactobacillus gasseri


N-acetylmuramic acid (MurNAc)-selective PTS transport system, MurP, IIBC, of 455 aas and 10 - 12 TMSs.

MurP of Bacillus velezensis


Glucose/fructose/glucosamine/mannose PTS IIABC system, FruA.  FruA phosphorylates the sugar subrates on the 6-hydroxyl group (Mazé et al. 2007).

FruA of Bifidobacterium breve


Fructooligosaccharide uptake porter of 651 aas and 10 TMSs, Pts1BCA (Chen et al. 2015).

Pts1CA of Lactobacillus plantarum


β-Glucoside (salicin, arbutin, cellobiose, etc) group translocator, BglF.  The bgl operon, encoding BglF, is regulated by antitermination when the RNA antiterminator protein, BglG, binds to one of two RAT sites in the mRNA (Gordon et al. 2015).

Bacteria; proteobacteria

BglF (IIBCAbgl) complex of E. coli


β-Glucoside [arbutin-salicin-cellobiose] (ASC) group translocator, AscF (Desai et al. 2010).

Bacteria; proteobacteria

AscF (IICBAsc complex) of E. coli


Trehalose porter, TreB (IIBC) which can take up maltose by facilitated diffusion (Decker et al. 1999).  Can also transport sucrose at a low rate (Steen et al. 2014).


Trehalose IIBC complex of E. coli

4.A.1.2.5β-glucoside (methyl-β-glucoside, salicin, arbutin) porter, BglF [a V317A or V317M mutation allows it to transport cellobiose as well] (Kotrba et al., 2003)Bacteriaβ-glucoside IIBCA (BglF) of Corynebacterium glutamicum
4.A.1.2.6β-glucoside (Aesculin/arbutin) porter, BglP (Cote et al., 2000; Cote and Honeyman, 2003)Bacteriaβ-glucoside IIBCA (BglP) of Streptococcus mutans (AAF89975)
4.A.1.2.7N-Acetylmuramic acid porter, MurP (YfeV) (Dahl et al., 2004)BacteriaN-Acetylmuramate IIBC (MurP or YfeV) of E. coli (P77272)

Trehalose porter, IIBC (TreP) (38% identical to 4.A.1.2.4) (Schöck and Dahl 1996; Ujiie et al. 2009).


TreP of Bacillus subtilis (P39794)

4.A.1.2.9Sucrose porter, IIBC (SacP) (55% identical to 4.A.1.2.1)BacteriaSacP of Bacillus subtilis (P05306)