Linked Life Data

16087673

Source:http://linkedlifedata.com/resource/pubmed/id/16087673

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
40
pubmed:dateCreated
2005-10-3
pubmed:abstractText
In Escherichia coli, the periplasmic disulfide oxidoreductase DsbA is thought to be a powerful but nonspecific oxidant, joining cysteines together the moment they enter the periplasm. DsbC, the primary disulfide isomerase, likely resolves incorrect disulfides. Given the reliance of protein function on correct disulfide bonds, it is surprising that no phenotype has been established for null mutations in dsbC. Here we demonstrate that mutations in the entire DsbC disulfide isomerization pathway cause an increased sensitivity to the redox-active metal copper. We find that copper catalyzes periplasmic disulfide bond formation under aerobic conditions and that copper catalyzes the formation of disulfide-bonded oligomers in vitro, which DsbC can resolve. Our data suggest that the copper sensitivity of dsbC- strains arises from the inability of the cell to rearrange copper-catalyzed non-native disulfides in the absence of functional DsbC. Absence of functional DsbA augments the deleterious effects of copper on a dsbC- strain, even though the dsbA- single mutant is unaffected by copper. This may indicate that DsbA successfully competes with copper and forms disulfide bonds more accurately than copper does. These findings lead us to a model in which DsbA may be significantly more accurate in disulfide oxidation than previously thought, and in which the primary role of DsbC may be to rearrange incorrect disulfide bonds that are formed during certain oxidative stresses.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
33785-91
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Copper stress causes an in vivo requirement for the Escherichia coli disulfide isomerase DsbC.
pubmed:affiliation
Program in Cellular and Molecular Biology, University of Michigan, 48109-1048, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, N.I.H., Extramural