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Construction and Analysis of LifsonRoig Models for the Helical Conformations of α-Peptides

✍ Scribed by Daniel S. Kemp

Publisher
John Wiley and Sons
Year
2002
Tongue
German
Weight
432 KB
Volume
85
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

New forms of Lifson____Roig algorithms are introduced for modeling stabilities of helices formed by polypeptides derived from α‐amino acids. The principles of constructing and generalizing these algorithms are developed, and their application to modeling of circular dichroism ellipticities and protection factors derived from H/D exchange of α‐peptide backbone amide residues are critically reviewed. With the aim of comparing the properties of structured conformations formed by α‐ and β‐peptides, the intrinsic limitations of Lifson____Roig algorithms and their underlying assumptions are analyzed. Lifson____Roig state sums that provide easy structural analysis are generated by new algorithms based on products of 8×8 and 16×16 matrices, and a simple protocol is introduced for generating new state sums that are tailored for specific purposes. The N‐ and C‐capping of highly helical α‐peptides by means of tailored helix‐stabilizing templates is shown to result in helical conformational manifolds that approach those of helical β‐peptides in conformational homogeneity.

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