Linked Life Data

8510142

Source:http://linkedlifedata.com/resource/pubmed/id/8510142

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-7-12
pubmed:abstractText
NAD and NADP are ubiquitous coenzymes in biological redox reactions. They have distinct metabolic functions, yet they differ only by an additional phosphate group esterified at the 2'-hydroxyl group of the AMP moiety of NADP. The natural specificity of Escherichia coli glutathione reductase for NADP has previously been converted into a marked preference for NAD by introducing seven point mutations into the beta alpha beta-fold of the NADP-binding domain of the protein based on the known structure of the human enzyme. Among them was the replacement of Ala179 by glycine (A179G) in the alpha-helix of the fold, a change suggested by a difference in a sequence fingerprint previously found in the dinucleotide-binding domains of a number of dehydrogenases. Although this position is at a distance of 10 A from the bound 2'-phosphate group of NADP in glutathione reductase, the A179G mutation was found to be synergistic and beneficial. We have now carried out X-ray crystallographic analyses of the NAD-dependent mutant without and with bound NADH. A comparison of the structures of the mutant and wild-type enzymes reveals a flip of the peptide bond between Gly174 and Ala175 such that the side-chain of another introduced amino acid, Glu197, is fixed and can participate in binding the adenine ribose of NAD, thereby contributing to the ability of the mutated enzyme to exert its selectivity for the "wrong" coenzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
231
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
191-5
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Structural differences between wild-type NADP-dependent glutathione reductase from Escherichia coli and a redesigned NAD-dependent mutant.
pubmed:affiliation
Institut für Organische Chemie und Biochemie der Universität, Freiburg, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't