NMR structure of Escherichia coli glutaredoxin 3-glutathione mixed disulfide complex: implications for the enzymatic mechanism.Nordstrand, K., slund, F., Holmgren, A., Otting, G., Berndt, K.D.
(1999) J.Mol.Biol. 286: 541-552
- PubMed: 9973569
- PubMed Abstract:
- Glutaredoxin-3 from Escherichia Coli. Amino Acid Sequence, 1H and 15N NMR Assignments, and Structural Analysis
Aslund, F.,Nordstrand, K.,Berndt, K.D.,Nikkola, M.,Bergman, T.,Ponstingl, H.,Jornvall, H.,Otting, G.,Holmgren, A.
(1996) J.Biol.Chem. 271: 6736
Glutaredoxins (Grxs) catalyze reversible oxidation/reduction of protein disulfide groups and glutathione-containing mixed disulfide groups via an active site Grx-glutathione mixed disulfide (Grx-SG) intermediate. The NMR solution structure of the Esc ...
Glutaredoxins (Grxs) catalyze reversible oxidation/reduction of protein disulfide groups and glutathione-containing mixed disulfide groups via an active site Grx-glutathione mixed disulfide (Grx-SG) intermediate. The NMR solution structure of the Escherichia coli Grx3 mixed disulfide with glutathione (Grx3-SG) was determined using a C14S mutant which traps this intermediate in the redox reaction. The structure contains a thioredoxin fold, with a well-defined binding site for glutathione which involves two intermolecular backbone-backbone hydrogen bonds forming an antiparallel intermolecular beta-bridge between the protein and glutathione. The solution structure of E. coli Grx3-SG also suggests a binding site for a second glutathione in the reduction of the Grx3-SG intermediate, which is consistent with the specificity of reduction observed in Grxs. Molecular details of the structure in relation to the stability of the intermediate and the activity of Grx3 as a reductant of glutathione mixed disulfide groups are discussed. A comparison of glutathione binding in Grx3-SG and ligand binding in other members of the thioredoxin superfamily is presented, which illustrates the highly conserved intermolecular interactions in this protein family.
Department of Medical Biochemistry and Biophysics, Karolinska Institute, S-171 77, Stockholm, Sweden.