| Literature DB >> 19534544 |
Russell W Driver1, Huy N Hoang, Giovanni Abbenante, David P Fairlie.
Abstract
A protein alpha-helix is defined by 3.6 amino acids per turn. Cyclization of the tripeptide Alanine-Leucine-Glutamate through a side chain to the N-terminus lactam bond produces cyclo-(1,3)-[ALE]-NH(2) which displays a circular dichroism spectrum typical of an alpha-helix backbone. However, proton NMR spectra show a novel cyclic peptide featuring two non-hydrogen-bonded antiparallel beta-strands connected by an Ala-Leu cis-amide bond. This example highlights that the common practice of characterizing alpha-helices by CD spectra alone can be misleading.Entities:
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Year: 2009 PMID： 19534544 DOI： 10.1021/ol901181b
Source DB: PubMed Journal: Org Lett ISSN： 1523-7052 Impact factor: 6.005