Peptidase S1A, polyserase-2 (IPR017326)

Short name: Pept_S1A_polyserase-2

Overlapping homologous superfamilies


Family relationships


This entry represents serine peptidases that belong to MEROPS petidase family S1A (clan PA(S)). They are a novel enzyme with three tandem serine protease domains in a single polypeptide chain. Polyserase-2 (polyserine protease-2) is the second identified human enzyme with several tandem serine protease domains. The first serine protease domain contains all characteristic features of these enzymes, whereas the second and third domains lack one residue of the catalytic triad of serine proteases and are predicted to be catalytically inactive. Both full-length polyserase-2 and its first serine protease domain hydrolyse synthetic peptides used for assaying serine proteases. The activity of the isolated domain was greater than that of the entire protein, suggesting that the two catalytically inactive serine protease domains of polyserase-2 may modulate the activity of the first domain. Polyserase-2 is expressed in foetal kidney, adult skeletal muscle, liver, placenta, prostate, and heart, and tumour cell lines derived from lung and colon adenocarcinomas. In contrast to polyserase-1, this protein is a secreted enzyme whose three protease domains remain as an integral parts of a single polypeptide chain [PMID: 15536082].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0004252 serine-type endopeptidase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.