Linked Life Data

2690937

Source:http://linkedlifedata.com/resource/pubmed/id/2690937

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1990-2-15
pubmed:abstractText
Cytochrome b5 has been genetically engineered to afford a fluorescent derivative capable of monitoring its association with cytochrome P-450cam from Pseudomonas putida [Stayton, P. S., Fisher, M. T., & Sligar, S. G. (1988) J. Biol. Chem. 263, 13544-13548]. In the mutant cytochrome b5, threonine is replaced by a cysteine at position 65 (T65C) and has been labeled with the environmentally sensitive fluorophore acrylodan. In this paper, the physiological P-450cam reductant putidaredoxin, an Fe2S2.Cys4 iron-sulfur protein, is shown to competitively inhibit the cytochrome b5 association, suggesting that cytochrome b5 and putidaredoxin bind to a similar site on the cytochrome P-450cam surface. Since the crystal structures for both cytochrome b5 and cytochrome P-450cam have been solved to high resolution, the complex has been computer modeled, and a good fit was found on the proximal surface of nearest approach to the P-450cam heme prosthetic group. The proposed model includes electrostatic contacts between conserved cytochrome b5 carboxylates Glu-44, Glu-48, Asp-60, and the exposed heme propionate with cytochrome P-450cam basic residues Lys-344, Arg-72, Arg-112, and Arg-364, respectively. Putidaredoxin has similarly been shown to contain a carboxylate-based binding surface, and the current results suggest that if the model is correct, then it also interacts at the proposed site, probably utilizing similar P-450cam electrostatic contacts.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8201-5
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Putidaredoxin competitively inhibits cytochrome b5-cytochrome P-450cam association: a proposed molecular model for a cytochrome P-450cam electron-transfer complex.
pubmed:affiliation
Department of Biochemistry University of Illinois, Urbana 61801.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't