Linked Life Data

17157186

Source:http://linkedlifedata.com/resource/pubmed/id/17157186

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2006-12-12
pubmed:abstractText
Human Cu,Zn-superoxide dismutase (hSOD1) has 4 cysteines per subunit. Cys57 and Cys148 are involved in an intrasubunit disulfide bond, while Cys6 and Cys111 are free. Cys6 is buried within the protein while Cys111 is on the surface, near the dimer interface. We examined by liquid chromatography-mass spectrometry the commercially purchased hSOD1 isolated from erythrocytes as well as hSOD1s isolated from human erythrocytes, brain, and hSOD1 expressed in Sf9, yeast, and E. coli. Our goal was to ascertain whether the Cys111 modification occurred naturally in vivo. Only the Sigma erythrocyte hSOD1 appeared to contain a trisulfide crosslink between the Cys111 residues. Thus it failed to react with N-ethylmaleimide, showed absorbtion at 325 nm that was eliminated by 2-mercaptoethanol, and had a mass 30 units more than expected for the native dimer. We examined the possibility that different purification methods might cause this modification in erythrocyte hSOD1. None of the procedures examined for hSOD1 purification produced such a trisulfide. In disagreement with Liu et al. [Biochemistry, 2000, 39, 8125-8132], complete derivitization of both Cys111s of hSOD1 from Sf9 cells with N-ethylmaleimide, 4-vinylpyridine, and by 5,5'-dithiobis(2-nitrobenzoic acid) were readily achieved; indicating that steric hindrance was not a problem.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0891-5849
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
41
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1837-46
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Modification of cysteine 111 in human Cu,Zn-superoxide dismutase.
pubmed:affiliation
Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural