Description
Cyclo(L-Leu-L-Pro) is a diketopiperazine metabolite that has been isolated from various bacterial and fungal species including
Streptomyces. It is active against twelve strains of vancomycin-resistant enterococci (VRE) with MIC values of 12.5 μg/ml for
E. faecalis strains K-99-34, K-00-184, and K-00-221. It also inhibits growth of K562, HL-60, and U937 leukemia cells in a concentration-dependent manner when used at concentrations of 1-500 μg/ml. Cyclo(L-Leu-L-Pro) also has antifouling activity, inhibiting attachment of
B. amphitrite larva with an EC
50 value of 0.15 mM.
