Phileucin-A cyclic dipeptide similar to phevalin (Aureusimine B) from Streptomyces coelicolor M1146

Abstract

Overexpression of a putative type III polyketide synthase (PKSIII) from the marine myxobacterium Enhygromyxa salina SWB007 in Streptomyces coelicolor M1146 led to the accumulation of a novel monoketopiperazine consisting of phenylalanine and isoleucine. This compound was named phileucin and shows high structural similarity to phevalin (aureusimine B). The protease inhibiting activity was tested against human cathepsin L, human leukocyte elastase, bovine trypsin and bovine chymotrypsin. In contrast to phevalin, no protease inhibition was observed.