PDBsum entry 2c0d

Oxidoreductase

PDB id: 2c0d

Contents

Protein chains

168 a.a. *

Waters ×280

* Residue conservation analysis

PDB id:

2c0d

Name:

Oxidoreductase

Title:

Structure of the mitochondrial 2-cys peroxiredoxin from plasmodium falciparum

Structure:

Thioredoxin peroxidase 2. Chain: a, b. Synonym: mitochondrial 2-cys peroxiredoxin. Engineered: yes

Source:

Plasmodium falciparum. Organism_taxid: 36329. Strain: 3d7. Expressed in: escherichia coli. Expression_system_taxid: 511693.

Biol. unit:

Dimer (from PDB file)

Resolution:

1.78Å R-factor: 0.167 R-free: 0.204

Authors:

I.W.Boucher,J.A.Brannigan,A.J.Wilkinson,A.M.Brzozowski,S.Muller

Key ref:

I.W.Boucher et al. (2006). Structural and biochemical characterization of a mitochondrial peroxiredoxin from Plasmodium falciparum. Mol Microbiol, 61, 948-959. PubMed id: 16879648

Date:

01-Sep-05 Release date: 21-Nov-06

Protein chains

Q8I5Q6  (Q8I5Q6_PLAF7) -  thioredoxin-dependent peroxiredoxin from Plasmodium falciparum (isolate 3D7)

Seq: 216 a.a.

Struc: 168 a.a.

Enzyme reactions

• Enzyme class: E.C.1.11.1.24 - thioredoxin-dependent peroxiredoxin.
• Reaction: a hydroperoxide + [thioredoxin]-dithiol = an alcohol + [thioredoxin]- disulfide + H2O

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

Added reference

Mol Microbiol 61:948-959 (2006)

PubMed id: 16879648

Structural and biochemical characterization of a mitochondrial peroxiredoxin from Plasmodium falciparum.

I.W.Boucher, P.J.McMillan, M.Gabrielsen, S.E.Akerman, J.A.Brannigan, C.Schnick, A.M.Brzozowski, A.J.Wilkinson, S.Müller.

ABSTRACT

Plasmodium falciparum possesses a single mitochondrion with a functional electron transport chain. During respiration, reactive oxygen species are generated that need to be removed to protect the organelle from oxidative damage. In the absence of catalase and glutathione peroxidase, the parasites rely primarily on peroxiredoxin-linked systems for protection. We have analysed the biochemical and structural features of the mitochondrial peroxiredoxin and thioredoxin of P. falciparum. The mitochondrial localization of both proteins was confirmed by expressing green fluorescent protein fusions in parasite erythrocytic stages. Recombinant protein was kinetically characterized using the cytosolic and the mitochondrial thioredoxin (PfTrx1 and PfTrx2 respectively). The peroxiredoxin clearly preferred PfTrx2 to PfTrx1 as a reducing partner, reflected by the KM values of 11.6 microM and 130.4 microM respectively. Substitution of the two dyads asparagine-62/tyrosine-63 and phenylalanine-139/alanine-140 residues by aspartate-phenylalaine and valine-serine, respectively, reduced the KM for Trx1 but had no effect on the KM of Trx2 suggesting some role for these residues in the discrimination between the two substrates. Solution studies suggest that the protein exists primarily in a homodecameric form. The crystal structure of the mitochondrial peroxiredoxin reveals a fold typical of the 2-Cys class peroxiredoxins and a dimeric form with an intermolecular disulphide bridge between Cys67 and Cys187. These results show that the mitochondrial peroxiredoxin of P. falciparum occurs in both dimeric and decameric forms when purified under non-reducing conditions.