Title | The structure of a triple mutant of pI258 arsenate reductase from Staphylococcus aureus and its 5-thio-2-nitrobenzoic acid adduct. |
Publication Type | Journal Article |
Year of Publication | 2004 |
Authors | Messens, J., I. Van Molle, P. Vanhaesebrouck, K. Van Belle, K. Wahni, J. C. Martins, L. Wyns, and R. Loris |
Journal | Acta Crystallogr D Biol Crystallogr |
Volume | 60 |
Issue | Pt 6 |
Pagination | 1180-4 |
Date Published | 2004 Jun |
ISSN | 0907-4449 |
Keywords | Arsenite Transporting ATPases, Crystallography, X-Ray, Dimerization, Disulfides, Electrons, Electrophoresis, Polyacrylamide Gel, Escherichia coli, Histidine, Ion Pumps, Mass Spectrometry, Models, Molecular, Multienzyme Complexes, Mutagenesis, Site-Directed, Mutation, Nitrobenzoates, Oxidation-Reduction, Protein Conformation, Protein Folding, Protein Structure, Secondary, Protein Structure, Tertiary, Staphylococcus aureus, Sulfhydryl Compounds |
Abstract | Structural insights into formation of the complex between the ubiquitous thiol-disulfide oxidoreductase thioredoxin and its oxidized substrate are under-documented owing to its entropical instability. In vitro, it is possible via a reaction with 5,5'-dithiobis-(2-nitrobenzoic acid) to make a stable mixed-disulfide complex between thioredoxin from Staphylococcus aureus and one of its substrates, oxidized pI258 arsenate reductase (ArsC) from S. aureus. In the absence of the crystal structure of an ArsC-thioredoxin complex, the structures of two precursors of the complex, the ArsC triple mutant ArsC C10SC15AC82S and its 5-thio-2-nitrobenzoic acid (TNB) adduct, were determined. The ArsC triple mutant has a structure very similar to that of the reduced form of wild-type ArsC, with a folded redox helix and a buried catalytic Cys89. In the adduct form, the TNB molecule is buried in a hydrophobic pocket and the disulfide bridge between TNB and Cys89 is sterically inaccessible to thioredoxin. In order to form a mixed disulfide between ArsC and thioredoxin, a change in the orientation of the TNB-Cys89 disulfide in the structure is necessary. |
DOI | 10.1107/S0907444904007334 |
Alternate Journal | Acta Crystallogr. D Biol. Crystallogr. |
PubMed ID | 15159594 |
- Log in to post comments
- Google Scholar
- PubMed
- DOI