Antiamoebin can function as a carrier or as a pore-forming peptaibol.

H Duclohier; C F Snook; B A Wallace

doi:10.1016/s0005-2736(98)00184-9

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Antiamoebin can function as a carrier or as a pore-forming peptaibol.

H Duclohier·C F Snook·B A Wallace

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Abstract

Antiamoebin is a 16-residue polypeptide whose crystal structure and lytic activity in membrane vesicles have recently been reported. It is a bent helical molecule and a member of the peptaibol family of antibiotics. Under conditions which produce voltage-dependent conductance activity by other members of the family, no single-channel conductance was detected for antiamoebin, and a carrier-like mechanism was put forward to account for its mode of action. We now present evidence for pore formation that is largely voltage-insensitive, with large amplitude single-channel events on top of a background conductance that may account for the previously proposed carrier-like activity. Thus, antiamoebin may be the first instance of a peptide which can function both as an ion carrier and a pore former.

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Amino Acid Sequence Anti-Bacterial Agents Carrier Proteins Ion Channel Gating Lipid Bilayers Molecular Sequence Data Peptaibols Peptides Journal Article Research Support, Non-U.S. Gov't

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H Duclohier, C F Snook, B A Wallace. 1998-12-09. Antiamoebin can function as a carrier or as a pore-forming peptaibol.. https://doi.org/10.1016/s0005-2736(98)00184-9

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