A Plant-like Biosynthesis of Benzoyl-CoA in the Marine Bacterium ‘Streptomyces maritimus’

The first plant-like biosynthesis of benzoic acid in a prokaryote, the marine actinomycete ‘Streptomyces maritimus’, has been characterized. Feeding experiments with 2H- and 13C-labeled intermediates revealed that phenylalanine is metabolized to benzoyl-coenzyme A (CoA) by means of a phenylalanine ammonia lyase and subsequent β-oxidation of cinnamoyl-CoA. Benzoyl-CoA serves as the rare starter unit of a type II polyketide synthase producing the structurally novel bacteriostatic polyketides enterocin and the wailupemycins. The results from the feeding study are consistent with the proposed biosynthetic model deduced from the cloned enterocin biosynthesis gene cluster.