Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1997-7-14
pubmed:databankReference
pubmed:abstractText
The gene encoding Desulfovibrio desulfuricans Norway cytochrome c3 (Mr 26,000), a dimeric octaheme cytochrome belonging to the polyheme cytochrome c3 superfamily, has been cloned and successfully expressed in another sulfate reducing bacteria, D. desulfuricans G201. The gene, named cycD, is monocistronic and encodes a cytochrome precursor of 135 amino acids with an extension at the NH2 terminus of 24 amino acids. This extension acts as a signal sequence which allows export across the cytoplasmic membrane into the periplasmic space. Tyrosine 73, which is in a close contact with the histidine sixth axial ligand to the heme 4 iron atom, has been replaced by a glutamate residue using site-directed mutagenesis. The cytochrome mutant when expressed in D. desulfuricans G201, is correctly folded and matured. A global increase of the oxidoreduction potentials of about 50 mV is measured for the Y73E cytochrome. The mutation also has a strong influence on the interaction of the cytochrome with its redox partner, the hydrogenase. This suggests, like the tetraheme cytochrome c3 (Mr 13, 000), heme 4 is the interactive heme in the cytochrome-hydrogenase complex and that alteration of the heme 4 environment can greatly affect the electron transfer reaction with its redox partner.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15128-34
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
A single mutation in the heme 4 environment of Desulfovibrio desulfuricans Norway cytochrome c3 (Mr 26,000) greatly affects the molecule reactivity.
pubmed:affiliation
Unité de Bioénergétique et Ingéniérie des Protéines, IFR1-Centre National de la Recherche Scientifique, 13402 Marseille Cedex 20, France.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.