Zervamicins, a structurally characterised peptide model for membrane ion channels.

S Agarwalla; I R Mellor; M S Sansom; I L Karle; J L Flippen-Anderson; K Uma; K Krishna; M Sukumar; P Balaram

doi:10.1016/s0006-291x(05)80768-5

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PubMed · 1378732

Zervamicins, a structurally characterised peptide model for membrane ion channels.

S Agarwalla·I R Mellor·M S Sansom·I L Karle·J L Flippen-Anderson·K Uma·K Krishna·M Sukumar·P Balaram

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Abstract

Voltage dependent membrane channels are formed by the zervamicins, a group of alpha-aminoisobutyric acid containing peptides. The role of polar residues like Thr, Gln and Hyp in promoting helical bundle formation is established by dramatically reduced channel lifetimes for a synthetic apolar analog. Crystal structures of Leu1-zervamicin reveal association of bent helices. Polar contacts between convex faces result in an 'hour glass' like arrangement of an aqueous channel with a central constriction. The structure suggests that gating mechanisms may involve movement of the Gln11 carboxamide group. Gln3 may play a role in modulating the size of the channel mouth.

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Amino Acid Sequence Anti-Bacterial Agents Electric Conductivity Ion Channels Lipid Bilayers Models, Biological Models, Molecular Molecular Sequence Data Peptaibols Peptides Phosphatidylcholines Protein Conformation Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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S Agarwalla, I R Mellor, M S Sansom, I L Karle, J L Flippen-Anderson, K Uma, K Krishna, M Sukumar, P Balaram. 1992-07-15. Zervamicins, a structurally characterised peptide model for membrane ion channels.. https://doi.org/10.1016/s0006-291x(05)80768-5

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