Protein Family Models

The predicted protein-sorting transpeptidase that we call exosortase (see TIGR02602) has distinct subclasses that associated with different types of exopolysaccharide production loci. We designate this, the most common type so far, exosortase 1. We propose the gene symbol xrtA, analogous to srtA for the most common type of sortase in Gram-positive bacteria.

Gene:

xrtA

Date:

2024-03-21

This family of proteins is functionally uncharacterised. This protein is found in bacteria. Proteins in this family are typically between 223 to 526 amino acids in length. This protein is found associated with Pfam:PF09721. (from Pfam)

Date:

2023-12-12

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

exsortase I with an EpsI family domain which may be involved in exopolysaccharide biosynthesis

Date:

2020-01-03

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

In Methylobacillus sp strain 12S, EpsI is encoded immediately downstream of the multiple-membrane-spanning putative transporter EpsH, and is predicted to be a periplasmic protein involved in, but not required for, expression of the exopolysaccharide methanolan. In a number of other species, protein homologous to EpsI is encoded either next to EpsH or, more often, combined in a fused gene. We have proposed renaming EpsH, or the EpsHI fusion protein, to exosortase, based on its phylogenetic association with the PEP-CTERM proposed protein targeting signal.

Date:

2024-01-16

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