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Reciprocity of steric and stereoelectronic effects in the collagen triple helix.

ABSTRACT: In previous work, we demonstrated that 4-fluoroproline residues can contribute greatly to the conformational stability of the collagen triple helix, and that this stability arises from stereoelectronic effects that fix the pucker of the pyrrolidine ring and thereby preorganize the backbone properly for triple-helix formation. Here, we take a reciprocal approach, demonstrating that the steric effect of a 4-methyl group confers stability similar to that from a 4-fluoro group in the opposite configuration. Such fundamental interplay between steric and stereoelectronic effects is heretofore unknown in proteins-natural or synthetic-and provides a new means to modulate conformational stability.

SUBMITTER: Shoulders MD

PROVIDER: S-EPMC2517127 | biostudies-literature | 2006 Jun

REPOSITORIES: biostudies-literature

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Reciprocity of steric and stereoelectronic effects in the collagen triple helix.

Shoulders Matthew D MD Hodges Jonathan A JA Raines Ronald T RT

Journal of the American Chemical Society 20060601 25

In previous work, we demonstrated that 4-fluoroproline residues can contribute greatly to the conformational stability of the collagen triple helix, and that this stability arises from stereoelectronic effects that fix the pucker of the pyrrolidine ring and thereby preorganize the backbone properly for triple-helix formation. Here, we take a reciprocal approach, demonstrating that the steric effect of a 4-methyl group confers stability similar to that from a 4-fluoro group in the opposite config ...[more]

PMID: 16787056

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