Direct NMR observation of the Cys-14 thiol proton of reduced Escherichia coli glutaredoxin-3 supports the presence of an active site thiol-thiolate hydrogen bond
1999 (English)In: FEBS Letters, ISSN 0014-5793, E-ISSN 1873-3468, Vol. 449, no 2-3, 196-200 p.Article in journal (Refereed) PublishedText
The active site of Escherichia coli glutaredoxin-3 (Grx3) consists of two redox active cysteine residues in the sequence -C-11-P-Y-C-14-H-. The H-1 NMR resonance of the cysteine thiol proton of Cys-14 in reduced Grx3 is observed at 7.6 ppm. The large downfield shift and NOEs observed with this thiol proton resonance suggest the presence of a hydrogen bond with the Cvs-ll thiolate, which is shown to have an abnormally low pK(a) value. A hydrogen bond would also agree,vith activity data of Grx3 active site mutants. Furthermore, the activity is reduced in a Grx3 H15V mutant, indicating electrostatic contributions to the stabilization of the Cys-ll thiolate, (C) 1999 Federation of European Biochemical Societies.
Place, publisher, year, edition, pages
1999. Vol. 449, no 2-3, 196-200 p.
crystal-structures, cxxc motif, dsba, enzyme mechanism, functional-characterization, glutaredoxin, glutathione, mixed disulfide, oxidoreductases, pig-liver thioltransferase, reactivity, thiol pk(a), thioredoxin
IdentifiersURN: urn:nbn:se:sh:diva-29036DOI: 10.1016/S0014-5793(99)00401-9ISI: 000080081200021PubMedID: 10338131ScopusID: 2-s2.0-0032959801OAI: oai:DiVA.org:sh-29036DiVA: diva2:891583
Times Cited: 16 Article English Cited References Count: 33 192lw2016-01-072016-01-072016-01-11Bibliographically approved