Antihistoplasmal in vitro and in vivo effect of Lys-Nva-FMDP.

The new synthetic antifungal agent, L-Lysyl-L-Norvalyl-FMDP, inhibits growth of the yeast form of Histoplasma capsulatum. The compound is transported into the fungal cells by peptide permeases, cleaved intracellularly to constitutive amino acids, and the released C-terminal amino acid inhibits glucosamine-6-phosphate synthase. Promising antihistoplasmal in vivo activity of the FMDP-peptide was observed in an organ load test in mice.