Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2007-3-12
pubmed:abstractText
The Fet3 protein from Saccharomyces cerevisiae is a multicopper oxidase with specificity toward Fe(II) and Cu(I). Fet3p turnover of Fe(II) supports high affinity iron uptake across the yeast plasma membrane, whereas its turnover of Cu(I) contributes to copper resistance in yeast. The structure of Fet3p has been used to identify possible amino acid residues responsible for this protein's reactivity with Cu(I), and structure-function analyses have confirmed this assignment. Fet3p Met(345) is required for the enzyme's reactivity toward Cu(I). Although the Fet3pM345A mutant exhibits wild type spectral and electrochemical behavior, the kinetic constants for Cu(I) turnover and for single-turnover electron transfer from Cu(I) to the enzyme are significantly reduced. The specificity constant with Cu(I) as substrate is reduced by one-fifth, whereas the electron transfer rate from Cu(I) is reduced 50-fold. This mutation has little effect on the reactivity toward Fe(II), indicating that Met(345) contributes specifically to Fet3p reactivity with the cuprous ion. These kinetic defects render the Fet3pM345A unable to support wild type cellular copper resistance, suggesting that there is a finely tuned copper redox balance at the yeast plasma membrane.
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
16
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7862-8
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Structure-function analysis of the cuprous oxidase activity in Fet3p from Saccharomyces cerevisiae.
pubmed:affiliation
Department of Biochemistry, School of Medicine and Biomedical Sciences, The University at Buffalo, Buffalo, New York 14214, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural