Abstract
Cyclodipeptide synthases (CDPSs) are a recently described family of enzymes that employ aminoacyl charged tRNAs in the biosynthesis of diketopiperazines. Fewer than a dozen CDPSs have been characterized to date. Bioinformatics analysis revealed two putative CDPSs in the genome of a marine actinomycete,
Nocardiopsis
sp. (CMB-M0232). These CDPSs were cloned and expressed in
E. coli
. Chemical extracts from these recombinant
E. coli
were analyzed by LC/MS, revealing both CDPSs catalyze production of cyclodipeptides including cyclo (L-Trp-L-Trp). These CDPSs are putative enzymes in biosynthesis of nocardioazine A, a prenylated anticancer diketopiperazine.
Fig. 1