All intermediates of the arsenate reductase mechanism, including an intramolecular dynamic disulfide cascade
AUTOR(ES)
Messens, Joris
FONTE
National Academy of Sciences
RESUMO
The mechanism of pI258 arsenate reductase (ArsC) catalyzed arsenate reduction, involving its P-loop structural motif and three redox active cysteines, has been unraveled. All essential intermediates are visualized with x-ray crystallography, and NMR is used to map dynamic regions in a key disulfide intermediate. Steady-state kinetics of ArsC mutants gives a view of the crucial residues for catalysis. ArsC combines a phosphatase-like nucleophilic displacement reaction with a unique intramolecular disulfide bond cascade. Within this cascade, the formation of a disulfide bond triggers a reversible “conformational switch” that transfers the oxidative equivalents to the surface of the protein, while releasing the reduced substrate.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=124290Documentos Relacionados
- Arsenate Reductase, Mycothiol, and Mycoredoxin Concert Thiol/Disulfide Exchange*S⃞
- Thiol–disulfide exchange is involved in the catalytic mechanism of peptide methionine sulfoxide reductase
- SPASTICITY: MECHANISM, MEASUREMENT, MANAGEMENT
- Genetic identification of a respiratory arsenate reductase
- Rubisco Synthesis, Assembly, Mechanism, and Regulation.