On the existence of an amphotericin B – sterol complex in lipid vesicles and in propanol–water systems

Abstract

The amphotericin B (AmB)-ergosterol complex, formed by interaction of the antibiotic with ergosterol-containing phospholipid vesicles, is associated with the lipid bilayer. It has been shown by circular dichroism studies that the AmB-ergosterol complex formed in water-propanol binary mixtures has a similar structure to that observed in phospholipid vesicles. A positive cooperativity is found for the interaction of AmB with ergosterol. The similar AmB-cholesterol complex is much less table and rearranges rapidly to a different conformation.