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The conducting form of gramicidin A is a right-handed double-stranded double helix.

ABSTRACT: The linear pentadecapeptide antibiotic, gramicidin D, is a naturally occurring product of Bacillus brevis known to form ion channels in synthetic and natural membranes. The x-ray crystal structures of the right-handed double-stranded double-helical dimers (DSDH) reported here agree with 15N-NMR and CD data on the functional gramicidin D channel in lipid bilayers. These structures demonstrate single-file ion transfer through the channels. The results also indicate that previous crystal structure reports of a left-handed double-stranded double-helical dimer in complex with Cs+ and K+ salts may be in error and that our evidence points to the DSDH as the major conformer responsible for ion transport in membranes.

SUBMITTER: Burkhart BM

PROVIDER: S-EPMC23667 | biostudies-literature | 1998 Oct

REPOSITORIES: biostudies-literature

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The conducting form of gramicidin A is a right-handed double-stranded double helix.

Burkhart B M BM Li N N Langs D A DA Pangborn W A WA Duax W L WL

Proceedings of the National Academy of Sciences of the United States of America 19981001 22

The linear pentadecapeptide antibiotic, gramicidin D, is a naturally occurring product of Bacillus brevis known to form ion channels in synthetic and natural membranes. The x-ray crystal structures of the right-handed double-stranded double-helical dimers (DSDH) reported here agree with 15N-NMR and CD data on the functional gramicidin D channel in lipid bilayers. These structures demonstrate single-file ion transfer through the channels. The results also indicate that previous crystal structure ...[more]

PMID: 9789021

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