Summary for clan MC

Summary Alignment Structure Literature
Clan type peptidaseM14.001 - carboxypeptidase A1 (Bos taurus), MEROPS Accession MER0001191 (peptidase unit: 111-419); PDB accession 3CPA
HistoryPEPTIDAS.TXT (SwissProt document)
DescriptionWater nucleophile; water bound by single zinc ion ligated to His, Glu (within the motif HXXE) and His
Contents of clanClan MC contains family M14, in which the peptidases in which are predominantly metallocarboxypeptidases, ad M86, containing poly-gamma-glutamate hydrolases.
EvidenceTertiary structures that have been determined for peptidases in family M14 show a fold that MEROPS considers to represent a distinctive structure when taken together with presence of a single zinc atom. The fold shows some similarity to those of metallopeptidases in families M17 and M28, in which two zinc atoms are essential for activity (Artymiuk et al., 1992; Makarova & Grishin, 1999). The similarity is especially marked in the central beta sheet. However, the relative positions of the zinc ligands are not conserved between families M14, M17 and M28, and accordingly family M14 is the only one assigned to clan MC.
Protein foldThe first crystal structure determined was for carboxypeptidase B (M14.003, Schmid & Herriott, 1976). Peptidases in clan MC are alpha/beta proteins with a beta/alpha/beta sandwich. The beta sheet has eight strands (in the order 23415867) and strands 3, 6 and 7 are antiparallel to the others. Peptidases in clans MF and MH have similar folds, but contain two metal ions.
Homologous non-peptidase familiesN-acetylmuramoyl-L-alanine amidase CwlV from Paenibacillus polymyxa has a similar fold to peptidases in clan MC (see PDB entry 1JWQ).
Other databases PFAMCL0035


Family Family Type Peptidase Structure
M14 carboxypeptidase A1 (Homo sapiens) Yes
M86 PghP gamma-polyglutamate hydrolase (bacteriophage) (Bacillus phage phiNIT1) Yes
M99 Csd4 peptidase ({Helicobacter pylori}) (Helicobacter pylori) -

Distribution of clan MC among Kingdoms of Organisms