Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2003-3-10
pubmed:abstractText
Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the transfer of electrons from reduced cytochrome c to molecular oxygen. COX assembly requires the coming together of nuclear- and mitochondrial-encoded subunits and the assistance of a large number of nuclear gene products acting at different stages of maturation of the enzyme. In Saccharomyces cerevisiae, expression of cytochrome c, encoded by CYC1 and CYC7, is required not only for electron transfer but also for COX assembly through a still unknown mechanism. We have attempted to distinguish between a functional and structural requirement of cytochrome c in COX assembly. A cyc1/cyc7 double null mutant strain was transformed with the cyc1-166 mutant gene (Schweingruber, M. E., Stewart, J. W., and Sherman, F. (1979) J. Biol. Chem. 254, 4132-4143) that expresses stable but catalytically inactive iso-1-cytochrome c. The COX content of the cyc1/cyc7 double mutant strain harboring non-functional iso-1-cytochrome c has been characterized spectrally, functionally, and immunochemically. The results of these studies demonstrate that cytochrome c plays a structural rather than functional role in assembly of cytochrome c oxidase. In addition to its requirement for COX assembly, cytochrome c also affects turnover of the enzyme. Mutants containing wild type apocytochrome c in mitochondria lack COX, suggesting that only the folded and mature protein is able to promote COX assembly.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8881-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:12522138-Alleles, pubmed-meshheading:12522138-Apoproteins, pubmed-meshheading:12522138-Catalysis, pubmed-meshheading:12522138-Cell Division, pubmed-meshheading:12522138-Cell Nucleus, pubmed-meshheading:12522138-Cytochrome c Group, pubmed-meshheading:12522138-Cytochromes c, pubmed-meshheading:12522138-DNA, pubmed-meshheading:12522138-Electron Transport Complex IV, pubmed-meshheading:12522138-Endopeptidase K, pubmed-meshheading:12522138-Fungal Proteins, pubmed-meshheading:12522138-Mitochondria, pubmed-meshheading:12522138-Mutation, pubmed-meshheading:12522138-Oxygen, pubmed-meshheading:12522138-Phenotype, pubmed-meshheading:12522138-Plasmids, pubmed-meshheading:12522138-Protein Folding, pubmed-meshheading:12522138-Saccharomyces cerevisiae, pubmed-meshheading:12522138-Spectrophotometry, pubmed-meshheading:12522138-Temperature, pubmed-meshheading:12522138-Time Factors
pubmed:year
2003
pubmed:articleTitle
Cytochrome oxidase assembly does not require catalytically active cytochrome C.
pubmed:affiliation
Department of Biological Sciences, Columbia University, New York, New York, 10027, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't