A biosynthetic gene cluster for the acetyl-CoA carboxylase inhibitor andrimid

Increasing bacterial resistance to antibiotics with conventional targets has focused attention on antibiotics with unconventional targets. One promising candidate, the acetyl-CoA carboxylase (ACC) inhibitor andrimid, is a potent, broad-spectrum antibiotic with high selectivity for prokaryotic ACC. Here, we report the use of a DNA-based approach to clone the andrimid biosynthetic gene cluster from Pantoea agglomerans, yielding a cosmid that confers robust andrimid production on Escherichia coli. This gene cluster encodes a hybrid nonribosomal peptide/polyketide (NRP/PK) synthase with several unusual features, including three enzymes that form and insert beta-phenylalanine, two transglutaminase-like enzymes that likely serve as condensation catalysts, and four densely hybrid modules that form the succinimide precursor. Unlike most type I NRPSs and PKSs, the andrimid gene cluster is a dissociated system comprised of small proteins. Therefore, future efforts can exploit the genetic manipulability of E. coli to engineer the andrimid synthase with the goal of producing a diverse set of andrimid analogues for clinical evaluation.