Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-7-26
pubmed:abstractText
The conformational properties of the competitive angiotensin II antagonist sarmesin [Sar-Arg-Val-Tyr(Me)-His-Pro-Phe] and its heptapeptide analogue [des1]sarmesin in dimethylsulphoxide-d6 were investigated by nuclear Overhauser effect (NOE) enhancement studies. Assignment of all backbone and side-chain protons was possible by combining information from intraresidue NOE studies with two-dimensional correlated spectroscopy (COSY) studies. Saturation of the His C alpha proton of sarmesin produced essentially the same interresidue NOE enhancement of the two Pro C delta protons, illustrating the presence of the trans His-Pro bond. Saturation of the Sar N-methyl group caused enhancement of one of the His C beta protons, suggesting the presence of a turn in the N-terminal region of the molecule. Saturation of His C2 in sarmesin and [des1]sarmesin enhanced the Tyr(Me) methyl signal. Saturation of the Tyr(Me) methyl protons in [des1]sarmesin produced NOE enhancement of the His C2 and C4 protons, and saturation of the His C2 proton enhanced the Tyr(Me) meta and ortho proton signals. Interresidue interactions between the Tyr(Me) and His protons in sarmesin and [des1]sarmesin illustrate that these two side-chains remain in close proximity even in the absence of the postulated hydrogen bond between Tyr hydroxyl and the His imidazole ring in angiotensin II. The data suggest a preferred conformation for sarmesin in DMSO in which the peptide backbone is S-shaped and similar to that for angiotensin II.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0196-9781
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
367-74
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:articleTitle
1H-NMR studies of sarmesin and [des1]sarmesin conformation in dimethylsulfoxide by nuclear Overhauser effect (NOE) enhancement spectroscopy: folding of the N- and C-terminal domains.
pubmed:affiliation
Department of Medical Biochemistry, University of Calgary, Alberta, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't