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Updated: Jun 21, 2026

Transmembrane Domain Oligomerization Propensity determined by ToxR Assay
Published on: May 26, 2011
Is the gramicidin a transmembrane channel single-stranded or double-stranded helix? A simple unequivocal
Abstract:
Thallium ion-induced carbonyl carbon chemical shifts were compared for all of the L-residue-peptide carbonyl carbons of the gramicidin A transmembrane channel. Molecular structures were deduced by using the argument that helically equivalent and equally proximal carbonyls would exhibit essentially equivalent ion-induced chemical shifts. The transmembrane channel was found to be a head-to-head dimer with the structure of a left-handed, single-stranded beta-helix.
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