Unknown

Dataset Information

0

Alanine is helix-stabilizing in both template-nucleated and standard peptide helices.


ABSTRACT: Alanine-based peptides of defined sequence and length show measurable helix contents, allowing them to be used as a model system both for analyzing the mechanism of helix formation and for investigating the contributions of side-chain interactions to protein stability. Extensive characterization of many peptide sequences with varying amino acid contents indicates that the favorable helicity of alanine-based peptides can be attributed to the large helix-stabilizing propensity of alanine. Based on their analysis of alanine-rich sequences N-terminally linked to a synthetic helix-inducing template, Kemp and coworkers [Kemp, D. S., Boyd, J. G. & Muendel, C. C. (1991) Nature (London) 352, 451-454; Kemp, D. S., Oslick, S. L. & Allen, T. J. (1996) J. Am. Chem. Soc. 118, 4249-4255] argue that alanine is helix-indifferent, however, and that the favorable helix contents of alanine-based peptides must have some other explanation. Here, we show that the helix contents of template-nucleated sequences are influenced strongly by properties of the template-helix junction. A model in which the helix propensities of residues at the template-peptide junction are treated separately brings the results from alanine-based peptides and template-nucleated helices into agreement. The resulting model provides a physically plausible resolution of the discrepancies between the two systems and allows the helix contents of both template-nucleated and standard peptide helices to be predicted by using a single set of helix propensities. Helix formation in both standard peptides and template-peptide conjugates can be attributed to the large intrinsic helix-forming tendency of alanine.

SUBMITTER: Rohl CA 

PROVIDER: S-EPMC22354 | biostudies-literature | 1999 Mar

REPOSITORIES: biostudies-literature

altmetric image

Publications

Alanine is helix-stabilizing in both template-nucleated and standard peptide helices.

Rohl C A CA   Fiori W W   Baldwin R L RL  

Proceedings of the National Academy of Sciences of the United States of America 19990301 7


Alanine-based peptides of defined sequence and length show measurable helix contents, allowing them to be used as a model system both for analyzing the mechanism of helix formation and for investigating the contributions of side-chain interactions to protein stability. Extensive characterization of many peptide sequences with varying amino acid contents indicates that the favorable helicity of alanine-based peptides can be attributed to the large helix-stabilizing propensity of alanine. Based on  ...[more]

Similar Datasets

| S-EPMC4820057 | biostudies-literature
| S-EPMC10900202 | biostudies-literature
| S-EPMC3236033 | biostudies-literature
| S-EPMC122184 | biostudies-literature
| S-EPMC5321054 | biostudies-literature
| S-EPMC1168409 | biostudies-other
| S-EPMC3043081 | biostudies-literature
| S-EPMC7839445 | biostudies-literature
| S-EPMC4956526 | biostudies-other
| S-EPMC1937538 | biostudies-literature