Linked Life Data

9571100

Source:http://linkedlifedata.com/resource/pubmed/id/9571100

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-6-4
pubmed:abstractText
Nitroxide spin labels, in conjunction with electron spin resonance (ESR) experiments, are extensively employed to probe the structure and dynamics of biomolecules. One of the most ubiquitous spin labeling reagents is the methanethiosulfonate spin label which attaches a spin label selectively to Cys residues via a disulfide bond (Cys-SL). However, the actual effect of the nitroxide spin label upon the conformation of the peptide or protein cannot be unambiguously determined by ESR. In this study, a series of 16-residue Ala-rich helical peptides was characterized by nuclear magnetic resonance techniques. The C alpha H chemical shift analysis, NOEs, and 3JNH alpha coupling constants for peptides with no Cys, free Cys, and Cys-SL (with the N-O group reduced) were compared. These results indicate that while replacement of an Ala with a Cys residue causes a loss of overall helical structure, the Cys-SL residue is helix supporting, as would be expected for a non-beta-branched aliphatic amino acid. Thus, the Cys-SL residue does not perturb helical structure and, instead, exhibits helix-stabilizing characteristics similar to that found for Ala, Met, and Leu.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1090-7807
pubmed:author
pubmed:issnType
Print
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
248-53
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
An NMR investigation of the conformational effect of nitroxide spin labels on Ala-rich helical peptides.
pubmed:affiliation
Department of Chemistry and Biochemistry, University of California, Santa Cruz 95064, USA.
pubmed:publicationType
Journal Article, Comparative Study