Peptidase M15B/M15C (IPR003709)

Short name: Pept_M15B/M15C

Domain relationships


Metalloproteases are the most diverse of the four main types of protease, with more than 50 families identified to date. In these enzymes, a divalent cation, usually zinc, activates the water molecule. The metal ion is held in place by amino acid ligands, usually three in number. The known metal ligands are His, Glu, Asp or Lys and at least one other residue is required for catalysis, which may play an electrophillic role. Of the known metalloproteases, around half 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].

These proteins are metallopeptidases belonging to MEROPS peptidase family M15 (clan MD), subfamily M15B (vanY D-Ala-D-Ala carboxypeptidase) and M15C (Ply, L-alanyl-D-glutamate peptidase).

Acquired VanA- and VanB-type glycopeptide resistance in enterococci is due to synthesis of modified peptidoglycan precursors terminating in D-lactate. As opposed to VanA-type strains which are resistant to both vancomycin and teicoplanin, VanB-type strains remain teicoplanin susceptible [PMID: 8631706]. The vanY gene was necessary for synthesis of the vancomycin-inducible D,D-carboxypeptidase EC: activity previously proposed to be responsible for glycopeptide resistance. However, this activity was not required for peptidoglycan synthesis in the presence of glycopeptides [PMID: 1398115].

Bacteriophage lysins (Ply) or endolysins are phage-encoded cell wall lytic enzymes which are synthesised late during virus multiplication and mediate the release of progeny virions. Bacteriophages of the pathogen Listeria monocytogenes encode endolysin enzymes which specifically hydrolyse the cross-linking peptide bridges in Listeria peptidoglycan. Ply118 is a 30.8kDa L-alanoyl-D-glutamate peptidase and Ply511 (36.5 kDa) acts as N-acetylmuramoyl-L-alanine amidase (IPR002502).

GO terms

Biological Process

GO:0006508 proteolysis

Molecular Function

GO:0008233 peptidase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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