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The genes encoding the entire cluster, epoA, epoB, epoC, epoD, epoE, and epoF, were redesigned and synthesized to allow for expression in Escherichia coli. The design of the synthetic epothilone genes together with Escherichia coli expression provides the ideal platform for both the biochemical investigation of the epothilone polyketide synthase and the generation of novel biosynthetic epothilone analogues.

Research has been conducted on catalytic triad which consists of serine, tyrosine and lysine residues. The study of these residues identified in ketoreductase domains of modular polyketide synthase has been carried out via the construction of point mutations for the amino acid residues in ketoreductase domains and the determination of its effect on ketoreduction, and the results are reported.

The engineered coenzyme B(sub)12-dependent methylmalonyl-CoA mutase--epimerase pathway produces the (2S)-methylmalonyl-CoA extender unit from the succinyl-CoA, instead of prppionyl-CoA as in the propionyl-CoA carboxylase. Isotopic labeling reveals that in the synthesis of polyketide, the starter and extender units are separately derived from exogenous propionate and methylmalonyl-CoA, respectively.

The role of the aldo-keto reductase (AKR) proteins from Micromonospora megalomicea in the biosynthesis of dTDP-L-mycarose is examined. High levels of mycarosyl-erythronolide B are produced, thus confirming the role of MegBIIa and MegBIIb proteins in this metabolic pathway.