Metallocarboxypeptidase inhibitor (IPR021142)

Short name: MCPI

Overlapping homologous superfamilies

Family relationships



This family represents the metallocarboxypeptidase inhibitor (MCPI) from potatoes, which belongs to the MEROPS inhibitor family I37, clan IE. It inhibits metallopeptidases belonging to MEROPS peptidase family M14, carboxypeptidase A. In Russet Burbank potatoes, it is a mixture of approximately equal amounts of two polypeptide chains containing 38 or 39 amino acid residues. The chains differ in their amino terminal sequence only [PMID: 1122280] and are resistant to fragmentation by proteases [PMID: 444453]. The structure of the complex between bovine carboxypeptidase A and the 39-amino-acid carboxypeptidase A inhibitor from potatoes has been determined at 2.5-A resolution [PMID: 6933511].

The potato inhibitor is synthesised as a precursor, having a 29 residue N-terminal signal peptide, a 27 residue pro-peptide, the 39 residue mature inhibitor region and a 7 residue C-terminal extension. The 7 residue C-terminal extension is involved in inhibitor inactivation and may be required for targeting to the vacuole where the mature active inhibitor accumulates [PMID: 9862450].

Contributing signatures

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