Linked Life Data

20840079

Source:http://linkedlifedata.com/resource/pubmed/id/20840079

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2010-11-15
pubmed:abstractText
Prxs (peroxiredoxins) are a ubiquitous family of cysteine-dependent peroxidases that react rapidly with H2O2 and alkyl hydroperoxides and provide defence against these reactive oxidants. Hydroperoxides are also formed on amino acids and proteins during oxidative stress, and they too are a potential cause of biological damage. We have investigated whether Prxs react with amino acid, peptide and protein hydroperoxides, and whether the reactions are sufficiently rapid for these enzymes to provide antioxidant protection against these oxidants. Isolated Prx2, which is a cytosolic protein, and Prx3, which resides within mitochondria, were reacted with a selection of hydroperoxides generated by ?-radiolysis or singlet oxygen, on free amino acids, peptides and proteins. Reactions were followed by measuring the accumulation of disulfide-linked Prx dimers, via non-reducing SDS/PAGE, or the loss of the corresponding hydroperoxide, using quench-flow and LC (liquid chromatography)/MS. All the hydroperoxides induced rapid oxidation, with little difference in reactivity between Prx2 and Prx3. N-acetyl leucine hydroperoxides reacted with Prx2 with a rate constant of 4 × 10(4) M-1 · s-1. Hydroperoxides present on leucine, isoleucine or tyrosine reacted at a comparable rate, whereas histidine hydroperoxides were ~10-fold less reactive. Hydroperoxides present on lysozyme and BSA reacted with rate constants of ~100 M-1 · s-1. Addition of an uncharged derivative of leucine hydroperoxide to intact erythrocytes caused Prx2 oxidation with no concomitant loss in GSH, as did BSA hydroperoxide when added to concentrated erythrocyte lysate. Prxs are therefore favoured intracellular targets for peptide/protein hydroperoxides and have the potential to detoxify these species in vivo.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Amino Acids, http://linkedlifedata.com/resource/pubmed/chemical/Dipeptides, http://linkedlifedata.com/resource/pubmed/chemical/Glutathione, http://linkedlifedata.com/resource/pubmed/chemical/Hydrogen Peroxide, http://linkedlifedata.com/resource/pubmed/chemical/Isoleucine, http://linkedlifedata.com/resource/pubmed/chemical/Leucine, http://linkedlifedata.com/resource/pubmed/chemical/PRDX2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/PRDX3 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Peptides, http://linkedlifedata.com/resource/pubmed/chemical/Peroxides, http://linkedlifedata.com/resource/pubmed/chemical/Peroxiredoxin III, http://linkedlifedata.com/resource/pubmed/chemical/Peroxiredoxins, http://linkedlifedata.com/resource/pubmed/chemical/Singlet Oxygen
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1470-8728
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
432
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
313-21
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Removal of amino acid, peptide and protein hydroperoxides by reaction with peroxiredoxins 2 and 3.
pubmed:affiliation
Free Radical Research Group, Department of Pathology, University of Otago, Christchurch, New Zealand. alexander.peskin@otago.ac.nz
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural