ID   2.3.1.289
DE   aureothin polyketide synthase system.
AN   aureothin polyketide synthase complex.
CA   4 (S)-methylmalonyl-CoA + 4-nitrobenzoyl-CoA + 8 H(+) + malonyl-CoA +
CA   4 NADPH = 5 CO2 + 6 CoA + demethylluteothin + 3 H2O + 4 NADP(+).
CC   -!- This polyketide synthase, characterized from the bacterium
CC       Streptomyces thioluteus, generates the backbone of the antibiotic
CC       aureothin.
CC   -!- It is composed of 4 modules that total 18 domains and is encoded by
CC       three genes.
CC   -!- The enzyme accepts the unusual starter unit 4-nitrobenzoyl-CoA and
CC       extends it by 4 molecules of (S)-methylmalonyl-CoA and a single
CC       molecule of malonyl-CoA.
CC   -!- The first module (encoded by aurA) is used twice in an iterative
CC       fashion, so that the five Claisen condensation reactions are
CC       catalyzed by only four modules.
CC   -!- The iteration becomes possible by the transfer of the [acp]-bound
CC       polyketide intermediate back to the ketosynthase (KS) domain on the
CC       opposite polyketide synthase strand (polyketides are homodimeric).
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