Purification from placenta, amino acid sequence, structure comparisons and cDNA cloning of human glutaredoxin
1995 (English)In: European Journal of Biochemistry, ISSN 0014-2956, E-ISSN 1432-1033, Vol. 227, no 1-2, 27-34 p.Article in journal (Refereed) Published
Glutaredoxin is generally a glutathione-dependent hydrogen donor for ribonucleotide reductase and also catalyses general glutathione (GSH)-disulfide-oxidoreduction reactions in the presence of NADPH and glutathione reductase. A Glutaredoxin from human placenta was purified to homogeneity, as judged by SDS/PAGE and IEF (12 kDa). Purification was monitored by the activity with hydroxyethyl disulfide as a substrate. Values of pI for glutaredoxin were obtained by IEF; the pI of the protein shifted from 7.3 in its fully reduced state to 9.0 in the oxidized state after treatment with excess hydroxyethyl disulfide. The glutaredoxin preparation showed GSH-dependent hydrogen-donor activity with recombinant mouse ribonucleotide reductase, it exhibited dehydroascorbate reductase activity as well as hydroxyethyl-disulfide-reducing activity. The amino acid sequence (residues 3-104) of glutaredoxin was determined by peptide sequencing and residues 1, 2 and 105 by cDNA sequence analysis. The glutaredoxin sequence comprised the classical active site for glutaredoxins -Cys22-Pro-Tyr-Cys25- and three additional half-cystine residues; two of these in positions 78 and 82. The sequence was similar to other known mammalian glutaredoxins (about 80% identities), with important differences such as one additional Cys residue (Cys7) and no Met residue. The sequence of human glutaredoxin was compared to that of Escherichia coli glutaredoxin with known three-dimensional structure in solution to identify conserved residues and predict a structure from alignment. In particular the GSH-binding site of glutaredoxin was conserved between all molecules. A cDNA that encodes the entire glutaredoxin gene (grx) and flanking sequences was isolated from a human spleen cDNA library. The nucleotide sequence of this cDNA (0.8 kb) was determined, including the complete grx gene.
Place, publisher, year, edition, pages
Wiley-Blackwell, 1995. Vol. 227, no 1-2, 27-34 p.
Glutathione-disulfide oxidoreductase; active-site disulfide; electron transfer; redox regulation; enzyme purification ; primary structure
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-98853DOI: 10.1111/j.1432-1033.1995.tb20356.xPubMedID: 7851394OAI: oai:DiVA.org:liu-98853DiVA: diva2:656005