Protein Family Models

ESPR (Extended Signal Peptide Region) is found in type V secretion system (T5SS) system proteins. Many such proteins are virulence factors, such autotransporter adhesins YapH (Yersinia pestis), FdeC (Escherhical coli), and BapA (Bartonella henselae), and autotransporter toxins such as VacA (Helicobacter pylori), SepA (Shigella flexneri), and Vat (Escherichia coli).

Date:

2024-08-14

Secretion of protein products occurs by a number of different pathways in bacteria. One of these pathways known as the type V pathway was first described for the IgA1 protease [2]. The protein component that mediates secretion through the outer membrane is contained within the secreted protein itself, hence the proteins secreted in this way are called autotransporters. This family corresponds to the presumed integral membrane beta-barrel domain that transports the protein. This domain is found at the C terminus of the proteins it occurs in. The N terminus contains the variable passenger domain that is translocated across the membrane. Once the passenger domain is exported it is cleaved auto-catalytically in some proteins, in others a different protease is used and in some cases no cleavage occurs [1]. [1]. 9778731. The great escape: structure and function of the autotransporter. proteins.. Henderson IR, Navarro-Garcia F, Nataro JP;. Trends Microbiol 1998;6:370-378.. [2]. 3027577. Gene structure and extracellular secretion of Neisseria. gonorrhoeae IgA protease.. Pohlner J, Halter R, Beyreuther K, Meyer TF;. Nature 1987;325:458-462.. [3]. 11980709. Export of autotransported proteins proceeds through an. oligomeric ring shaped by C-terminal domains.. Veiga E, Sugawara E, Nikaido H, de Lorenzo V, Fernandez LA;. EMBO J 2002;21:2122-2131.. [4]. 15014442. Structure of the translocator domain of a bacterial. autotransporter.. Oomen CJ, Van Ulsen P, Van Gelder P, Feijen M, Tommassen J, Gros. P;. EMBO J 2004;23:1257-1266. (from Pfam)

Date:

2024-08-14

This family consists of immunoglobulin A1 protease proteins. The immunoglobulin A1 protease cleaves immunoglobulin IgA and is found in pathogenic bacteria such as Neisseria gonorrhoeae [3]. Not all of the members of this family are IgA proteases Swiss:O32555 from E. coli O157:H7 cleaves human coagulation factor V [2] and Swiss:O88093 is a hemoglobin protease from E. coli EB1 [1]. [1]. 9743528. Characterization of a hemoglobin protease secreted by the. pathogenic Escherichia coli strain EB1.. Otto BR, van Dooren SJ, Nuijens JH, Luirink J, Oudega B;. J Exp Med 1998;188:1091-1103.. [2]. 9194704. EspP, a novel extracellular serine protease of. enterohaemorrhagic Escherichia coli O157:H7 cleaves human. coagulation factor V.. Brunder W, Schmidt H, Karch H;. Mol Microbiol 1997;24:767-778.. [3]. 3027577. Gene structure and extracellular secretion of Neisseria. gonorrhoeae IgA protease.. Pohlner J, Halter R, Beyreuther K, Meyer TF;. Nature 1987;325:458-462. (from Pfam)

Date:

2024-08-14

A number of Gram-negative bacterial proteins, mostly found in pathogens and associated with virulence, contain a conserved C-terminal domain that integrates into the outer membrane and enables the N-terminal region to be delivered across the membrane. This C-terminal autotransporter domain is about 400 amino acids in length and includes the aromatic amino acid-rich OMP signal, typically ending with a Phe or Trp residue, at the extreme C-terminus.

Date:

2024-06-21