TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*1.B.38.1.1









Large non-selective MSP porin of 574 aas, with short lived large ion conduction (Mathers et al. 1996). Contains  MOSP_N and MOSP_C domains which exists as periplasmic hydrophilic monomers and trimeric porins, respectively. MOSP_C, destined for the OM, follows the canonical BAM pathway, but formation of a stable periplasmic conformer of MOSP_N involves an export-related, folding pathway not present in E. coli (Puthenveetil et al. 2017).

Bacteria
Spirochaetes
Msp of Treponema denticola
*1.B.38.1.2









Treponema repeat protein K (TprK), an outer membrane surface exposed variable antigen which plays a role in immune evasion and persistence (Giacani et al. 2012; Reid et al. 2014).

Bacteria
Spirochaetes
TprK of Treponema pallidum
*1.B.38.1.3









Repeat protein, TprEb

Bacteria
Spirochaetes
Repeat protein, TprEb
*1.B.38.1.4









Major outer membrane sheath protein, Msp or MOSP, of 543 aas.  Msp has a bipartide structure and exists as periplasmic and outer membrane-integrated trimeric conformers (Anand et al. 2013).  The N-terminal domain (residues 77 - 286) does not insert into the membrane, but the C-terminal domain (residues 332 - 543) does to form pores (Anand et al. 2013).  It resembles the surface exposed variable antigen, TprK (Giacani et al. 2012) which plays roles in immune evasion and persistence.  MOSP is one of its principal cell surface virulence determinants. Bioinformatics predicts that MOSP consists of N- and C-terminal domains, MOSPN and MOSPC. Biophysical analysis of constructs refolded in vitro demonstrated that MOSPC, which has porin activity, forms amphiphilic trimers, while MOSPN forms an extended hydrophilic monomer (Puthenveetil et al. 2017). It is a also a pore-forming cytotoxin that inserts into animal cell membranes (see TC# 1.C.128.1.1), and is a constituent of the outer membrane lipoprotein-protease complex of the Dentilisin Family (TC# 9.B.355).

Bacteria
Spirochaetes
Major outer sheath protein, Msp, of Treponema denticola
*1.B.38.1.5









Outer membrane bipartite trimeric porin of 598 aas with an N-terminal MOSPN domain (in the periplasm), and a C-terminal MOSPC domain (cell surface localized), TprC/TprD.  The MOSPN domain confers envelope integrity by anchoring the C-terminal porin domain to periplasmic structural constituents (Anand et al. 2015). Selection pressures exerted within human populations drive T. pallidum subsp. pallidum TrpC diversity by mutation of loop regions and by recombination(Kumar et al. 2018).

Bacteria
Spirochaetes
TprC of Treponema pallidum
*1.B.38.1.6









Outer membrane trimeric porin, TprI of 598 aas with a structure similar to that of TprC (TC# 1.B.38.1.5) (Anand et al. 2015).

Bacteria
Spirochaetes
TprI of Treponema pallidum
*1.B.38.1.7









SusD of 502 aas and 1 N-terminal TMS.

Bacteria
Bacteroidetes
SusD of Bacteroides fragilis
*1.B.38.1.8









Uncharacterized major outer membrane protein of 511 aas and 1 N-terminal TMS.

Bacteria
Spirochaetes
UP of Treponema vincentii
*1.B.38.1.9









Outer membrane pore-forming TprA protein of 607 aas. This protein is 91% identical to the TprA protein of T. pallidum.

Bacteria
Spirochaetes
TprA of Treponema paraluiscuniculi
*1.B.38.1.10









SusD protein of 570 aas and 1 N-terminal TMS (Joglekar et al. 2018).

Bacteria
Bacteroidetes
SusD of Bacteroides thetaiotaomicron
*1.B.38.2.1









Putative outer membrane protein of 460 aas. Shows some sequence similarity to autotransporters (1.B.40)

Bacteria
Spirochaetes
OMP of Spirochaeta thermophila
*1.B.38.2.2









Putative outer membrane protein of 446 aas.  Shows some sequence similiarity to autotransporters (1.B.40)

Bacteria
Spirochaetes
OMP of Spirochaeta thermophila
*1.B.38.2.3









Uncharacterized porin of 389 aas and 1 N-terminal TMS.

Bacteria
Spirochaetes
UP of Spirochaetae bacterium
*1.B.38.2.4









Uncharacterized protein of 469 aas.

Bacteria
Spirochaetes
UP of Spirochaeta perfilievii
*1.B.38.3.1









Putative sheath protein of 520 aas with 14 putative β-TMSs at the N-terminus and a fairly long C-terminal extension.

Bacteria
Spirochaetes
Putative sheath protein of Treponema brennaborense
*1.B.38.3.2









Putative outer membrane protein of 575 aas and 24 putative β-TMSs, MspA

Bacteria
Spirochaetes
MspA of Treponema maltophilum
*1.B.38.3.3









Putative outer membrane protein of 590 aas and 22 putative β-TMSs.

Bacteria
Spirochaetes
OMP of Treponema lecithinolyticum
*1.B.38.4.1









Outer membrane maltooligosaccharide uptake protein, SusE, of 387 aas and 1 N-terminal TMS.  It forms a complex with the SusC porin (TC# 1.B.14.6.1), the SusD porin (TC# 1.B.38.1.10), the SusF porin (TC# 1.B.38.4.2) and SusG (α-amylase; TC# 8.A.9.1.3) in the outer membrane (Foley et al. 2018).  The complex binds starch and maltooligosaccharides (Cho and Salyers 2001).

Bacteria
Bacteroidetes
OMP of Bacteroides thetaiotaomicron
*1.B.38.4.2









Outer membrane protein, SusF, of 485 aas and 1 N-terminal TMS.  The protein has an N-terminal DUF5115 domain followed by two C-terminal CBM-SusEF-like domains. SusF mediates starch-binding (or maltooligosaccharde-binding) before transport into the periplasm for further degradation. SusE and SusF do not constitute the major starch-binding proteins in the starch degradative pathway. SusF has lower affinity for starch compared to SusE (Shipman et al. 2000). The 3-d structure of the complex has been determined (Cameron et al. 2012). The SusCDEFG complex in the outer membrane is described in more detail in TC# 1.B.38.4.1 (Foley et al. 2018).

Bacteria
Bacteroidetes
OMP, SusF, of Bacteroides thetaiotaomicron
*1.B.38.4.3









SusE/F homologue of 347 aas and 1 N-terminal TMS.

Bacteria
Bacteroidetes
AusE of Pontibacter lucknowensis
*1.B.38.4.4









Uncharacterized DUF5115 domain-containing protein of 477 aas and 1 N-terminal TMS.

Bacteria
Bacteroidetes
UP of Chryseobacterium chaponense
*1.B.38.4.5









Uncharacterized SusD homologue of 531 aas and 1 N-terminal TMS.

Bacteria
Bacteroidetes
SusD homologue of Phaeodactylibacter xiamenensis