Family M32


Summary Holotypes Alignment Tree Genomes Structure Literature

Summary for family M32

NamePeptidase family M32 (carboxypeptidase Taq family)
Family type peptidaseM32.001 - carboxypeptidase Taq (Thermus aquaticus), MEROPS Accession MER0001186 (peptidase unit: 1-511)
Content of familyPeptidase family M32 contains metallocarboxypeptidases.
History Identifier created: Methods Enzymol. 248:183-228 (1995)
Catalytic typeMetallo
Active site residuesH276 E277 H280 E306 
Active siteFamily M32 members contain two zinc-binding histidines and a catalytic glutamate in an HEXXH zinc-binding motif - a motif that is most commonly found in zinc endopeptidases and aminopeptidases. The third zinc ligand is a glutamate found in an HES motif further toward the C-terminus.
Activities and specificitiesCarboxypeptidase Taq (M32.001) and carboxypeptidase Pfu (M32.002) are both stable up to high temperatures, and exhibit carboxypeptidase activity with broad specificities, except (in the case of carboxypeptidase Taq) when there is a proline at the C-terminus. Carboxypeptidase Taq (M32.001) hydrolyses amino acids with long side chains most readily (Motoshima & Kaminogawa, 2004).
Molecular structureThe structure of carboxypeptidase Pfu is homodimeric with each subunit being mostly helical (Arndt et al., 2002). The HEXXH motif is found at the bottom of a deep substrate binding groove formed by the two subunits. The structure was found to be to be similar to that of neurolysin (M03.002) (Arndt et al., 2002) and angiotensin-converting enzyme 2 (M02.004) (Natesh et al., 2003).
Basis of clan assignmentPredicted active site residues for members of this family and thermolysin, the type example for clan MA, occur in the motif HEXXH
Distribution of family Bacteria details  
Archaea details  
Protozoa details  
Fungi details  
Plants details  
Animals details  
Viruses -  
Biological functions
Statistics for family M32Sequences:1788
Identifiers with PDB entries:4
Downloadable files Sequence library (FastA format)
Sequence alignment (FastA format)
Phylogenetic tree (Newick format)
Peptidases and Homologues MEROPS ID Structure
carboxypeptidase TaqM32.001Yes
carboxypeptidase PfuM32.002Yes
TcMCP1 carboxypeptidaseM32.003Yes
TcMCP2 carboxypeptidase (Trypanosoma cruzi)M32.004-
LmaCP1 carboxypeptidase (Leishmania major) and similarM32.005-
ypwA peptidaseM32.006Yes
family M32 non-peptidase homologuesnon-peptidase homologue-
family M32 unassigned peptidasesunassigned-