Linked Life Data

17448901

Source:http://linkedlifedata.com/resource/pubmed/id/17448901

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2007-4-23
pubmed:abstractText
Reaction of radicals in the presence of O2, or singlet oxygen, with some amino acids, peptides, and proteins yields hydroperoxides. These species are key intermediates in chain reactions and protein damage. They can be detected in cells and are poorly removed by enzymatic defenses. Previously we have shown that peptide and protein hydroperoxides react rapidly with thiols, with this resulting in inactivation of some thiol-dependent enzymes. In light of these data, we hypothesized that inactivation of protein tyrosine phosphatases (PTPs), by hydroperoxides present on oxidized proteins, may contribute to cellular and tissue dysfunction by modulation of phosphorylation-dependent cell signaling. We show here that PTPs in cell lysates, and purified PTP-1B, are inactivated by amino acid, peptide, and protein hydroperoxides in a concentration- and structure-dependent manner. Protein hydroperoxides are particularly effective, with inhibition occurring with greater efficacy than with H2O2. Inactivation involves reaction of the hydroperoxide with the conserved active-site Cys residue of the PTPs, as evidenced by hydroperoxide consumption measurements and a diminution of this effect on blocking the Cys residue. This inhibition of PTPs, by oxidized proteins containing hydroperoxide groups, may contribute to cellular dysfunction and altered redox signaling in systems subject to oxidative stress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0891-5849
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1543-51
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Inhibition of protein tyrosine phosphatases by amino acid, peptide, and protein hydroperoxides: potential modulation of cell signaling by protein oxidation products.
pubmed:affiliation
The Heart Research Institute, 114 Pyrmont Bridge Road, Camperdown, NSW 2050, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't