Protein Family Models

Members of this family include several paralogous, LPXTG-anchored surface zinc-dependent metallo-endopeptidases of Streptococcus, including ZmpA (Iga), ZmpB, and ZmpC, the first of which contributes to pathgenesis by cleaving host Iga1. Most family members also contain a domain described by PF05342 upstream of this domain.

Date:

2024-10-16

This domain is found in a wide range of extracellular proteins. It is found tandemly repeated in up to 8 copies. It is found in the N-terminus of peptidases belonging to the M26 family which cleave human IgA. The domain is also found in proteins involved in metabolism of bacterial cell walls suggesting this domain may have an adhesive function. [1]. 18992255. Crystal structure of the resuscitation-promoting factor (DeltaDUF)RpfB from M. tuberculosis. Ruggiero A, Tizzano B, Pedone E, Pedone C, Wilmanns M, Berisio R;. J Mol Biol. 2009;385:153-162. [2]. 15598841. The G5 domain: a potential N-acetylglucosamine recognition domain involved in biofilm formation. Bateman A, Holden MT, Yeats C;. Bioinformatics. 2005;21:1301-1303. (from Pfam)

Date:

2024-10-16

This domain occurs primarily in LPXTG sorting signal-containing streptococcal surface-anchored proteins that have the HEXXH motif of paralogous zinc-dependent metalloproteases such as Iga/ZmpA (which cleaves human IgA1), ZmpC (which cleaves human matrix metalloproteinase 9), and ZmpB. The HEXXH site essential to catalysis occurs in a more C-terminal domain described by PF07580.

Date:

2024-10-16

Many surface proteins found in Streptococcus, Staphylococcus, and related lineages share apparently homologous signal sequences. A motif resembling [YF]SIRKxxxGxxS[VIA] appears at the start of the transmembrane domain. The GxxS motif appears perfectly conserved, suggesting a specific function and not just homology. There is a strong correlation between proteins carrying this region at the N-terminus and those carrying the Gram-positive anchor domain with the LPXTG sortase processing site at the C-terminus. (from Pfam)

Date:

2024-08-14

Date:

2024-08-14

This model describes the LPXTG motif-containing region found at the C-terminus of many surface proteins of Streptococcus and Streptomyces species. Cleavage between the Thr and Gly by sortase or a related enzyme leads to covalent anchoring at the new C-terminal Thr to the cell wall. Hits that do not lie at the C-terminus or are not found in Gram-positive bacteria are probably false-positive. A common feature of this proteins containing this domain appears to be a high proportion of charged and zwitterionic residues immediatedly upstream of the LPXTG motif. This model differs from other descriptions of the LPXTG region by including a portion of that upstream charged region.

Date:

2021-04-27

The [YF]SIRKxxxGxxS type of signal peptide appears at the start of many proteins of Streptococcus, Staphylococcus, and Enterococcus, but not in other lineages such as Bacillus. Recent work in Staphylococcus aureus has shown that septal secretion (targeting to the crosswall in dividing cells) of the YSIRK-containing staphylococcal protein A depends on SecA, SecDF, and the lipoteichoic acid synthase LtaS, all of which co-purify when the motif is modified to YSIRKxxxGxxL to block processing.

Date:

2024-12-19