Structural snapshots along the reaction mechanism of the atypical poplar thioredoxin‐like2.1. Issue 6 (4th March 2018)

• Record Type: Journal Article
• Authors: Chibani, Kamel; Saul, Frederick; Didierjean, Claude; Rouhier, Nicolas; Haouz, Ahmed
• Is Part Of: FEBS letters. Volume 592:Issue 6(2018)
• Page Start: 1030
• Page End: 1041
• Publication Date: 2018-03-04
• Subjects: atypical thioredoxin -- crystal structure -- disulfide exchange -- glutathione -- Populus; Biochemistry -- Periodicals; Biophysics -- Periodicals; Molecular biology -- Periodicals; Biochimie -- Périodiques; Biochemistry; Biophysics; Molecular biology; Periodicals; 572.05
• DOI: 10.1002/1873-3468.13009
• Languages: English
• ISSNs: 0014-5793

Abstract

Abstract : Plastidial thioredoxin (TRX)‐like2.1 proteins are atypical thioredoxins possessing a WCRKC active site signature and using glutathione for recycling. To obtain structural information supporting the peculiar catalytic mechanisms and target proteins of these TRXs, we solved the crystal structures of poplar TRX‐like2.1 in oxidized and reduced states and of mutated variants. These structures share similar folding with TRXs exhibiting the canonical WCGPC signature. Moreover, the overall conformation is not altered by reduction of the catalytic disulfide bond or in a C45S/C67S variant that formed a disulfide‐bridged dimer possibly mimicking reaction intermediates with target proteins. Modeling of the interaction of TRX‐like2.1 with both NADPH‐ and ferredoxin‐thioredoxin reductases (FTR) indicates that the presence of Arg43 and Lys44 residues likely precludes reduction by the plastidial FTR. Abstract :