Peptidase S8/S53 domain superfamily
IPR036852
Definition
These proteins contain a domain superfamily found in serine peptidases belonging to the MEROPS peptidase families S8 (subfamilies S8A (subtilisin) and S8B (kexin) and S53 (sedolisin), both of which are members of clan SB PMID:8439290. The subtilisin family is one of the largest serine peptidase families characterised to date. Over 200 subtilises are presently known, more than 170 of which with their complete amino acid sequence PMID:9070434. It is widespread, being found in eubacteria, archaebacteria, eukaryotes and viruses PMID:7845208. The vast majority of the family are endopeptidases, although there is an exopeptidase, tripeptidyl peptidase [[cite:PMID:7845208], [cite:PMID:8439290]]. Structures have been determined for several members of the subtilisin family: they exploit the same catalytic triad as the chymotrypsins, although the residues occur in a different order (HDS in chymotrypsin and DHS in subtilisin), but the structures show no other similarity [[cite:PMID:7845208], [cite:PMID:8439290]]. Some subtilisins are mosaic proteins, while others contain N- and C-terminal extensions that show no sequence similarity to any other known protein PMID:7845208. The proprotein-processing endopeptidases kexin, furin and related enzymes form a distinct subfamily known as the kexin subfamily (S8B). These preferentially cleave C-terminally to paired basic amino acids. Members of this subfamily can be identified by subtly different motifs around the active site [[cite:PMID:7845208], [cite:PMID:8439290]]. Members of the kexin subfamily, along with endopeptidases R, T and K from the yeast Tritirachium and cuticle-degrading peptidase from Metarhizium, require thiol activation. This can be attributed to the presence of a cysteine near to the active site histidine PMID:8439290. Only one viral member of the subtilisin family is known, a 56kDa protease from herpes virus 1, which infects the channel catfish PMID:7845208.
11 human proteins with this domain
Each is a reviewed human protein in the Seroatlas serome and a potential autoantibody target; this domain groups them into one antibody-relevant category. Every entry links to its own record.
Loading the interactive Seroatlas explorer...