Linked Life Data

8626496

Source:http://linkedlifedata.com/resource/pubmed/id/8626496

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
14
pubmed:dateCreated
1996-6-21
pubmed:databankReference
pubmed:abstractText
We have determined the crystal structure of a complex between the noncompetitive inhibitor (Kis = 27 microM, Kii = 48 microM with respect to oxidized glutathione (GSSG) and Kis = 144 microM, Kii = 176 microM with respect to NADPH) 6-hydroxy-3-oxo-3H-xanthene-9-propionic acid (XAN) and human glutathione reductase (hGR). The structure, refined to an R-factor of 0.158 at 2.0 A resolution, reveals XAN bound in the large cavity present at the hGR dimer interface where it does not overlap the glutathione binding site. The inhibitor binding causes extensive local structural changes that primarily involve amino acid residues from a 30-residue alpha-helix that lines the cavity and contributes to the active site of hGR. Despite the lack of physical overlap of XAN with the GSSG binding site, no GSSG binding is seen in soaks carried out with high XAN and GSSG concentrations, suggesting that some subtle interaction between the sites exists. An earlier crystallographic analysis on the complex between hGR and 3,7-diamino-2,8-dimethyl-5-phenyl-phenazinium chloride (safranin) showed that safranin bound at this same site. We have found that safranin also inhibits hGR in a noncompetitive fashion, but it binds about 16 times less tightly (Kis = 453 microM, Kii = 586 microM with respect to GSSG) than XAN and does not preclude the binding of GSSG in the crystal. Although in structure-based drug design competitive inhibitors are usually targetted, XAN's binding to a well defined site that is unique to glutathione reductase suggests that noncompetitive inhibitors could also serve as lead compounds for structure-based drug design, in particular as components of chimeric inhibitors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8101-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Kinetics and crystallographic analysis of human glutathione reductase in complex with a xanthene inhibitor.
pubmed:affiliation
Section of Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, New York 14853, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't