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PubMed · 10380341

Basic conformers in beta-peptides.

K Möhle·R Günther·M Thormann·N Sewald·H J Hofmann
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Abstract

The conformation of oligomers of beta-amino acids of the general type Ac-[beta-Xaa]n-NHMe (beta-Xaa = beta-Ala, beta-Aib, and beta-Abu; n = 1-4) was systematically examined at different levels of ab initio molecular orbital theory (HF/6-31G*, HF/3-21G). The solvent influence was considered employing two quantum-mechanical self-consistent reaction field models. The results show a wide variety of possibilities for the formation of characteristic elements of secondary structure in beta-peptides. Most of them can be derived from the monomer units of blocked beta-peptides with n = 1. The stability and geometries of the beta-peptide structures are considerably influenced by the side-chain positions, by the configurations at the C alpha- and C beta-atoms of the beta-amino acid constituents, and especially by environmental effects. Structure peculiarities of beta-peptides, in particular those of various helix alternatives, are discussed in relation to typical elements of secondary structure in alpha-peptides.

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Amino AcidsDiamideModels, MolecularOligopeptidesProtein ConformationStereoisomerismStress, MechanicalJournal ArticleResearch Support, Non-U.S. Gov't

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K Möhle, R Günther, M Thormann, N Sewald, H J Hofmann. 1999. Basic conformers in beta-peptides.. https://doi.org/10.1002/(sici)1097-0282(199908)50%3A2%3C167%3A%3Aaid-bip6%3E3.0.co%3B2-m

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