Linked Life Data

8130251

Source:http://linkedlifedata.com/resource/pubmed/id/8130251

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1994-4-18
pubmed:abstractText
We have investigated electrogenic events and absorbance changes following pulsed illumination of partly reduced cytochrome c oxidase in the absence of dioxygen and carbon monoxide (Hallén et al. (1993) FEBS Lett. 318, 134-138). In both types of experiment similar kinetics were observed; a rapid (tau < 0.5 micros) change was followed by relaxations with time constants of approx. 7 micros and 80 micros. Both the time constant and the activation energy of the 80 micros component were, within the experimental error, the same as those of one of the steps in the reduction of dioxygen by reduced cytochrome c oxidase. The absorbance changes showed a rapid haem reduction, followed by reoxidation. They were affected by CN(-) and N(-)3, ligands which bind in the binuclear centre of cytochrome c oxidase; the absorbance changes were quenched by CN(-) and in the presence of N(-)3, the amplitude of the 7 micros component increased whereas that of the 80 micros decreased. Based on these findings, a model is proposed which involves electron transfer from Cu(+)B to Fe(3+)A3, as a response to structural changes upon pulsed illumination. The same structural changes are also suggested to take place in the oxygen reduction. These changes may play an important role in the gating of electrons as well as protons, an obligatory feature of a redox-linked proton pump.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
1184
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
207-18
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Light-induced structural changes in cytochrome c oxidase: implication for the mechanism of electron and proton gating.
pubmed:affiliation
Department of Biochemistry and Biophysics, Chalmers University of Technology, Göteborg, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't