Family

Peptidase M36, fungalysin (IPR001842)

Short name: Peptidase_M36

Overlapping homologous superfamilies

None.

Family 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 group of metallopeptidases belong to MEROPS peptidase family M36 (fungalysin family, clan MA(E)). The predicted active site residues for members of this family and thermolysin, the type example for clan MA, occur in the motif HEXXH.

Fungalysin is produced by fungi, Aspergillus and other species, to aid degradation of host lung cell walls on infection. The enzyme is a 42kDa single chain protein, with a pH optimum of 7.5-8.0 and optimal temperature of 60 celcius [PMID: 14766908].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0004222 metalloendopeptidase activity
GO:0008270 zinc ion binding

Cellular Component

GO:0005615 extracellular space

Contributing signatures

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