Domain

Peptidase M50 (IPR008915)

Short name: Peptidase_M50

Domain relationships

None.

Description

Over 70 metallopeptidase families have been identified to date. In these enzymes a divalent cation which is usually zinc, but may be cobalt, manganese or copper, activates the water molecule. The metal ion is held in place by amino acid ligands, usually three in number. In some families of co-catalytic metallopeptidases, two metal ions are observed in crystal structures ligated by five amino acids, with one amino acid ligating both metal ions. The known metal ligands are His, Glu, Asp or Lys. At least one other residue is required for catalysis, which may play an electrophillic role. Many metalloproteases contain an HEXXH motif, which has been shown in crystallographic studies to form part of the metal-binding site [PMID: 7674922]. The HEXXH motif is relatively common, but can be more stringently defined for metalloproteases as 'abXHEbbHbc', where 'a' is most often valine or threonine and forms part of the S1' subsite in thermolysin and neprilysin, 'b' is an uncharged residue, and 'c' a hydrophobic residue. Proline is never found in this site, possibly because it would break the helical structure adopted by this motif in metalloproteases [PMID: 7674922].

This entry contains metallopeptidases belonging to MEROPS peptidase family M50 (S2P protease family, clan MM).

Members of the M50 metallopeptidase family include: mammalian sterol-regulatory element binding protein (SREBP) site 2 protease, Escherichia coli protease EcfE, stage IV sporulation protein FB and various hypothetical bacterial and eukaryotic homologues. A number of proteins are classified as non-peptidase homologues as they either have been found experimentally to be without peptidase activity, or lack amino acid residues that are believed to be essential for the catalytic activity.

GO terms

Biological Process

GO:0006508 proteolysis

Molecular Function

GO:0004222 metalloendopeptidase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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