Trichogin GA IV, an antimicrobial peptaibol, exerts its function by augmenting membrane permeability, but the molecular aspects of its pore-forming mechanism are still debated. Several lines of evidence indicate a 'barrel-stave' channel structure, similar to that of alamethicin, but the length of a trichogin helix is too short to span a normal bilayer. Herein, we present electrophysiology measurements in planar bilayers, showing that trichogin does form channels of a well-defined size (R=4.2⋅10(9) Ω; corresponding at least to a trimeric aggregate) that span the membrane and allow ion diffusion, but do not exhibit voltage-dependent rectification, unlike those of alamethicin.
Iftemi, S., De Zotti, M., Formaggio, F., Toniolo, C., Stella, L., Luchian, T. (2014). Electrophysiology investigation of trichogin GA IV activity in planar lipid membranes reveals ion channels of well-defined size. CHEMISTRY & BIODIVERSITY, 11(7), 1069-1077 [10.1002/cbdv.201300334].
Electrophysiology investigation of trichogin GA IV activity in planar lipid membranes reveals ion channels of well-defined size
STELLA, LORENZO;
2014-01-01
Abstract
Trichogin GA IV, an antimicrobial peptaibol, exerts its function by augmenting membrane permeability, but the molecular aspects of its pore-forming mechanism are still debated. Several lines of evidence indicate a 'barrel-stave' channel structure, similar to that of alamethicin, but the length of a trichogin helix is too short to span a normal bilayer. Herein, we present electrophysiology measurements in planar bilayers, showing that trichogin does form channels of a well-defined size (R=4.2⋅10(9) Ω; corresponding at least to a trimeric aggregate) that span the membrane and allow ion diffusion, but do not exhibit voltage-dependent rectification, unlike those of alamethicin.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
