Protein Family Models

Members of this family are designated exosortase, analogous to sortase in cell wall sorting mediated by LPXTG domains in Gram-positive bacteria. The phylogenetic distribution of the proteins in this entry is nearly perfectly correlated with the distribution of the proteins having the PEP-CTERM anchor motif, IPR013424. Members of this entry are integral membrane proteins with eight predicted transmembrane helices in common. Some members of this family have long trailing sequences past the region described by this model. This model does not include the region of the first predicted transmembrane region. The best characterised member is EpsH of Methylobacillus sp. 12S, where it is part of a locus associated with biosynthesis of the exopolysaccharide methanol-an. (from Pfam)

Date:

2023-12-12

cyanoexosortase B (CrtB) is a transpeptidase similar to Nostoc punctiforme cyanoexosortase B that recognizes and modifies its substrate by proteolytic cleavage of a carboxyl-terminal (Pro-Glu-Phe) motif sorting signal

Date:

2018-07-06

This HMM describes a cyanobacterial-restricted form of exosortase, associated with a PEP-CTERM domain subclass described in model TIGR04155. This is one of two such cyanoexosortases, either of which is sufficient to accompany TIGR04155 family members. The other cyanoexosortase is TIGR03763 (crtA).

Gene:

crtB

Date:

2024-03-21

This model represents the most conserved region of the multitransmembrane protein family of exosortases and archaeosortases. The region includes nearly invariant motifs at the ends of three predicted transmembrane helices on the extracytoplasmic face: a Cys (often Cys-Xaa-Gly), Asn-Xaa-Xaa-Arg, and His. This model is much broader than the bacterial exosortase model (TIGR02602), and has in intended scope similar to (or broader than) Pfam model PF09721.

Date:

2024-03-21

This family is designated exosortase, and it is the predicted protein-sorting transpeptidase for the PEP-CTERM protein-sorting signal of many biofilm-producing Gram-negative bacteria. This system is analogous to the sortase/LPXTG system found mostly in Gram-positive bacteria. Members of this family are integral membrane proteins with eight predicted transmembrane helices in common, and with a triad of invariant residues that matches the catalytic triad of sortases. Some members of this family have long trailing sequences past the region described by this model, which in other species is a separate protein EpsI. This model does not include the region of the first predicted transmembrane region. The only partially characterized member is EpsH of Methylobacillus sp. 12S, part of a locus associated with biosynthesis of the exopolysaccharide methanolan but itself not involved in polysaccharide biosynthesis.

Gene:

xrt

Date:

2024-03-21