Effect of phospholipid enrichment on nystatin action: differences in antibiotic sensitivity between in vivo and in vitro conditions.

Polyene-nystatin had a selective effect on the transport of glutamic acid and lysine in phosphatidylcholine-, or phosphatidylethanolamine-enriched cells of Saccharomyces cerevisiae. However, liposomes prepared from lipid extracts from the same cells did not mimic the results of in vivo studies. Our in vitro results demonstrated that factors other than sterols, e.g. phospholipid enrichment, protein lipid interactions and lipid bilayer asymmetry may also affect the overall susceptibility of polyene antibiotics.