Linked Life Data

8427926

Source:http://linkedlifedata.com/resource/pubmed/id/8427926

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-3-5
pubmed:abstractText
The peptides Ac-delta Phe-Ala-delta Phe-NH-Me (1), Ac-delta Phe-Val-delta Phe-NH-Me (2), Ac-delta Phe-Gly-delta Phe-Ala-OMe (3), and Boc-Ala-delta Phe-Gly-delta Phe-Ala-OMe (4), containing two dehydro-phenylalanine (delta Phe) residues, were synthesized and the solution structure investigated in various solvents. The nmr and CD measurements indicate that all the dehydropeptides examined adopt 3(10)-helical conformations in solution. The tripeptides 1 and 2 exhibited an intense negative CD exciton couplet, which was assigned to the right-handed screw sense, while the tetrapeptide 3 displayed a CD couplet having opposite sign, which was assigned to the left-handed helical sense. In the pentapeptide 4 the sense of the helix was found to vary with solvent and temperature, as demonstrated by the sign reversal of the CD spectrum. The right-handed sense dominates in hexafluoro-2-propanol, whereas a left-handed helix prevails in chloroform, acetonitrile and methanol. A crucial role for this behavior is likely to be played by the two alanine residues positioned respectively at the head and tail of the sequence, which favor conformations having opposite screw senses.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-3525
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-10
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Solution structure of peptides containing two dehydro-phenylalanine residues: a CD investigation.
pubmed:affiliation
CNR-Institute of Biophysics, Pisa, Italy.
pubmed:publicationType
Journal Article, Comparative Study