Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2001-5-1
pubmed:abstractText
Midpoint reduction potentials for the flavin cofactors in human NADPH-cytochrome P450 oxidoreductase were determined by anaerobic redox titration of the diflavin (FAD and FMN) enzyme and by separate titrations of its isolated FAD/NADPH and FMN domains. Flavin reduction potentials are similar in the isolated domains (FAD domain E(1) [oxidized/semiquinone] = -286 +/- 6 mV, E(2) [semiquinone/reduced] = -371 +/- 7 mV; FMN domain E(1) = -43 +/- 7 mV, E(2) = -280 +/- 8 mV) and the soluble diflavin reductase (E(1) [FMN] = -66 +/- 8 mV, E(2) [FMN] = -269 +/- 10 mV; E(1) [FAD] = -283 +/- 5 mV, E(2) [FAD] = -382 +/- 8 mV). The lack of perturbation of the individual flavin potentials in the FAD and FMN domains indicates that the flavins are located in discrete environments and that these environments are not significantly disrupted by genetic dissection of the domains. Each flavin titrates through a blue semiquinone state, with the FMN semiquinone being most intense due to larger separation (approximately 200 mV) of its two couples. Both the FMN domain and the soluble reductase are purified in partially reduced, colored form from the Escherichia coli expression system, either as a green reductase or a gray-blue FMN domain. In both cases, large amounts of the higher potential FMN are in the semiquinone form. The redox properties of human cytochrome P450 reductase (CPR) are similar to those reported for rabbit CPR and the reductase domain of neuronal nitric oxide synthase. However, they differ markedly from those of yeast and bacterial CPRs, pointing to an important evolutionary difference in electronic regulation of these enzymes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1956-63
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Determination of the redox properties of human NADPH-cytochrome P450 reductase.
pubmed:affiliation
Department of Pure & Applied Chemistry, University of Strathclyde, The Royal College, 204 George Street, Glasgow, G1 1XL, UK. Andrew.Munro@strath.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't