Transport of antimicrobial agents using peptide carrier systems: anticandidal activity of m-fluorophenylalanine-peptide conjugates

Abstract

A series of di- and tripeptides containing D- and L-m-fluorophenylalanine was prepared and tested in vitro for the ability to inhibit the growth to the yeast Candida albicans. Peptides containing L-m-fluorophenylalanine inhibited the growth of C. albicans with minimum inhibitory concentrations (MIC) ranging from 0.5-63 .mu.g/ml. The parent L-m-fluorophenylalanine and peptides containing D-m-fluorophenylalaine were inactive (MIC > 250 .mu.g/ml) in these tests. The results of competitive antagonism studies supported peptide transport mediated entry of the inhibitory peptides, followed by release of L-m-fluorophenylalanine inside the cell.