Duclohier H, Snook C F, Wallace B A
UMR 6522 CNRS-Université de Rouen (IFRMP 23), Boulevard M. de Broglie, 76821 Mont-Saint-Aignan, France.
Biochim Biophys Acta. 1998 Dec 9;1415(1):255-60. doi: 10.1016/s0005-2736(98)00184-9.
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.
