Proline kinks in transmembrane alpha-helices.

G von Heijne

doi:10.1016/0022-2836(91)90695-3

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PubMed · 2016741

Proline kinks in transmembrane alpha-helices.

G von Heijne

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Abstract

Integral membrane proteins often contain proline residues in their presumably alpha-helical transmembrane segments. This is in marked contrast to globular proteins, where proline is rarely found inside alpha-helices. Proline residues cause kinks in helices, and, in addition to leaving the i-4 backbone carbonyl without its normal hydrogen bond donor, also sterically prevent the (i-3)-carbonyl-(i + l)-amide backbone hydrogen bond from forming. Here, some structural aspects of proline kinks in transmembrane helices are discussed on the basis of an analysis of Pro-kinked helices in the photosynthetic reaction center and bacteriorhodopsin, as well as results from an analysis of Pro-containing transmembrane segments identified in the NBRF Protein Sequence Databank.

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Amino Acid Sequence Bacteriorhodopsins Hydrogen Bonding Membrane Proteins Models, Chemical Molecular Sequence Data Photosynthetic Reaction Center Complex Proteins Proline Protein Conformation Journal Article Research Support, Non-U.S. Gov't

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G von Heijne. 1991-04-05. Proline kinks in transmembrane alpha-helices.. https://doi.org/10.1016/0022-2836(91)90695-3

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