PDBsum entry 3dwc

Hydrolase

PDB id: 3dwc

Contents

Protein chains

501 a.a. *

Ligands

SO4 ×13

GOL ×9

GLY-ALA

Metals

_CO ×4

Waters ×1120

* Residue conservation analysis

PDB id:

3dwc

Name:

Hydrolase

Title:

Trypanosoma cruzi metallocarboxypeptidase 1

Structure:

Metallocarboxypeptidase. Chain: a, b, c, d. Synonym: tcmcp-1. Engineered: yes

Source:

Trypanosoma cruzi. Organism_taxid: 5693. Gene: mcar-1. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.10Å R-factor: 0.180 R-free: 0.221

Authors:

G.Niemirowicz,D.Fernandez,M.Sola,J.J.Cazzulo,F.X.Aviles,F.X.Gomis- Ruth

Key ref:

G.Niemirowicz et al. (2008). The molecular analysis of Trypanosoma cruzi metallocarboxypeptidase 1 provides insight into fold and substrate specificity. Mol Microbiol, 70, 853-866. PubMed id: 18793339

Date:

22-Jul-08 Release date: 09-Sep-08

Protein chains

Q6ZXC0  (Q6ZXC0_TRYCR) -  Metallocarboxypeptidase from Trypanosoma cruzi

Seq: 503 a.a.

Struc: 501 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.3.4.17.19 - carboxypeptidase Taq.
• Reaction: Release of a C-terminal amino acid with broad specificity, except for -Pro.
• Cofactor: Zn(2+)

Mol Microbiol 70:853-866 (2008)

PubMed id: 18793339

The molecular analysis of Trypanosoma cruzi metallocarboxypeptidase 1 provides insight into fold and substrate specificity.

G.Niemirowicz, D.Fernández, M.Solà, J.J.Cazzulo, F.X.Avilés, F.X.Gomis-Rüth.

ABSTRACT

Trypanosoma cruzi is the aetiological agent of Chagas' disease, a chronic infection that affects millions in Central and South America. Proteolytic enzymes are involved in the development and progression of this disease and two metallocarboxypeptidases, isolated from T. cruzi CL Brener clone, have recently been characterized: TcMCP-1 and TcMCP-2. Although both are cytosolic and closely related in sequence, they display different temporary expression patterns and substrate preferences. TcMCP-1 removes basic C-terminal residues, whereas TcMCP-2 prefers hydrophobic/aromatic residues. Here we report the three-dimensional structure of TcMCP-1. It resembles an elongated cowry, with a long, deep, narrow active-site cleft mimicking the aperture. It has an N-terminal dimerization subdomain, involved in a homodimeric catalytically active quaternary structure arrangement, and a proteolytic subdomain partitioned by the cleft into an upper and a lower moiety. The cleft accommodates a catalytic metal ion, most likely a cobalt, which is co-ordinated by residues included in a characteristic zinc-binding sequence, HEXXH and a downstream glutamate. The structure of TcMCP-1 shows strong topological similarity with archaeal, bacterial and mammalian metallopeptidases including angiotensin-converting enzyme, neurolysin and thimet oligopeptidase. A crucial residue for shaping the S(1') pocket in TcMCP-1, Met-304, was mutated to the respective residue in TcMCP-2, an arginine, leading to a TcMCP-1 variant with TcMCP-2 specificity. The present studies pave the way for a better understanding of a potential target in Chagas' disease at the molecular level and provide a template for the design of novel therapeutic approaches.