It is shown that the fluctuation spectrum of the lipid bilayer conductance induced by one-sided application of polyene antibiotics has a profound l/f component with a magnitude being proportional to the single-channel conductance. The observed component is thought to be caused by the channel mobility increasing at one-sided polyene application in a comparison with two-sided application where a Lorentzian spectrum of fluctuations was found earlier.
View Article and Find Full Text PDFA mathematical model of the ionic channel permeable both to anions and cations is considered. The model takes into account the electrostatic interaction between oppositely charged ions and does not suppose single-file movement. An equation for zero-current potential is derived, which leads to the Goldman equation in the limit of low ion concentrations.
View Article and Find Full Text PDFSingle ionic channels of approximately 10 pS in magnitude and approximately 100 ms duration (in 2 M KCl solution) were recorded when amphotericin B (AB) was added to one side of a lipid bilayer. Using blocking ions it has been shown that these channels are asymmetrical half-pores (similar to those postulated by Marty and Finkelstein) which are capable of forming long-living symmetrical pores if AB is added to both sides of the membrane.
View Article and Find Full Text PDF