The interaction of penicillins with phospholipids

Abstract

Abstract The interaction of the antibiotics, penicillin G and ampicillin, with sonicated sols of phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine has been examined by Sephadex gel nitration and dynamic dialysis. Nuclear magnetic resonance spectroscopy provided evidence of a predominantly hydrophobic interaction between the antibiotics and the phospholipids, phosphatidylserine and phosphatidylcholine. Confirmation of hydrophobic interaction was provided by a rheological investigation of the effects of urea and guanidine hydrochloride on the antibiotic-phospholipid complex. Penicillin G was found to interact to a greater degree than ampicillin, a result which is of interest in the light of present knowledge of in vivo activity of these antibiotics.