Linked Life Data

10978350

Source:http://linkedlifedata.com/resource/pubmed/id/10978350

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2001-1-18
pubmed:abstractText
To study the essentiality of head domain movement of the Rieske iron-sulfur protein (ISP) during bc(1) catalysis, Rhodobacter sphaeroides mutants expressing His-tagged cytochrome bc(1) complexes with three pairs of cysteines engineered (one cysteine each) on the interface between cytochrome b and ISP, A185C(cytb)/K70C(ISP), I326C(cytb)/G165C(ISP), and T386C(cytb)/K164C(ISP), were generated and characterized. Formation of an intersubunit disulfide bond between cytochrome b and ISP is detected in membrane (intracytoplasmic membrane and air-aged chromatophore), and purified bc(1) complex was prepared from the A185C(cytb)/K70C(ISP) mutant cells. Formation of the intersubunit disulfide bond in this cysteine pair mutant complex is concurrent with the loss of its bc(1) activity. Reduction of this disulfide bond by beta-mercaptoethanol restores activity, indicating that mobility of the head domain of ISP is functionally important in the cytochrome bc(1) complex. The rate of intramolecular electron transfer, between 2Fe2S and heme c(1), in the A185C(cytb)/K70C(ISP) mutant complex is much lower than that in the wild type or in their respective single cysteine mutant complexes, indicating that formation of an intersubunit disulfide bond between cytochrome b and ISP arrests the head domain of ISP in the "fixed state" position, which is too far for electron transfer to heme c(1).
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
38597-604
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Confirmation of the involvement of protein domain movement during the catalytic cycle of the cytochrome bc1 complex by the formation of an intersubunit disulfide bond between cytochrome b and the iron-sulfur protein.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't