1RXE

ArsC complexed with MNB

Summary for 1RXE

• Entry DOI: 10.2210/pdb1rxe/pdb
• Related: 1LJL 1RXI
• Descriptor: Arsenate reductase, POTASSIUM ION, PERCHLORATE ION, ... (5 entities in total)
• Functional Keywords: arsc, mixed disulphide, 5-thio-2-nitrobenzoic acid, 5-mercapto-2-nitrobenzoic acid, tnb, mnb, oxidoreductase
• Biological source: Staphylococcus aureus
• Total number of polymer chains: 1
• Total formula weight: 15105.27

Authors

Messens, J.,Van Molle, I.,Vanhaesebrouck, P.,Limbourg, M.,Van Belle, K.,Wahni, K.,Martins, J.C.,Loris, R.,Wyns, L. (deposition date: 2003-12-18, release date: 2004-06-01, Last modification date: 2024-10-30)

Primary citation

Messens, J.,Van Molle, I.,Vanhaesebrouck, P.,Van Belle, K.,Wahni, K.,Martins, J.C.,Wyns, L.,Loris, R.
The structure of a triple mutant of pI258 arsenate reductase from Staphylococcus aureus and its 5-thio-2-nitrobenzoic acid adduct.
Acta Crystallogr.,Sect.D, 60:1180-1184, 2004

PubMed 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.

PubMed: 15159594
DOI: 10.1107/S0907444904007334

Experimental method

X-RAY DIFFRACTION (1.7 Å)