Peptidase M18 (IPR001948)

Short name: Peptidase_M18

Family relationships


This group of metallopeptidases belong to the MEROPS peptidase family M18, (clan MH). The proteins have two catalytic zinc ions at the active site, bound by His/Asp, Asp, Glu, Asp/Glu and His. The catalysed reaction involves the release of an N-terminal aminoacid, usually neutral or hydrophobic, from a polypeptide [PMID: 7674922].

The type example is aminopeptidase I from Saccharomyces cerevisiae (Baker's yeast), the sequence of which has been deduced, and the mature protein shown to consist of 469 amino acids [PMID: 2651436]. A 45-residue presequence contains both positively- and negatively-charged and hydrophobic residues, which could be arranged in an N-terminal amphiphilic alpha-helix [PMID: 2651436]. The presequence differs from signal sequences that direct proteins across bacterial plasma membranes and endoplasmic reticulum or into mitochondria. It is unclear how this unique presequence targets aminopeptidase I to yeast vacuoles, and how this sorting utilises classical protein secretory pathways [PMID: 2651436].

GO terms

Biological Process

GO:0006508 proteolysis

Molecular Function

GO:0004177 aminopeptidase activity
GO:0008270 zinc ion binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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