Research Interests
The research interests of my group lie at the interface of chemistry and biology. We focus on generating complex biologically active compounds, such as polyketides, non-ribosomal peptides, and complex sugars. To make these molecules, we use two complementary, but very different methods—synthetic chemistry and metabolic engineering—which are unified by their reliance on a deep understanding of the biosynthetic origin of the target molecule.
Biosynthetic pathways often take advantage of intrinsically favorable reaction pathways in the formation of complex molecules. We identify these putative pathways and use their favorable, spontaneous chemistry as key elements in our total synthesis efforts. This provides us with rapid and elegant synthetic routes and allows us to experimentally test our proposed biosyntheses. We are currently involved in the biomimetic total syntheses of two complex polyketides—laulimalide and spiculoic acid.
Fermentation has many advantages over chemical synthesis in the production of large quantities of complex molecules, including scalability, cost, and environmental impact. Unfortunately, many desired compounds are not currently available through fermentation. Using known biosynthetic enzymes, we are engineering lab-friendly bacteria to produce new complex molecules. Our current focus is on developing an E. coli system for the overproduction of sialic acid and a Myxococcus xanthus system for the overproduction of polyketides.
Engineered biosynthetic pathways cannot yet be constructed to generate any desired complex molecule. In polyketide biosynthesis there are still many structural elements whose biosynthetic origins remain a mystery. By identifying and biochemically characterizing the enzymes or catalytic domains responsible for formation of these structural elements, we lay the foundation for their future incorporation into engineered biosynthetic pathways. We are currently working on characterizing thioesterase domains responsible for formation of macrodiolides (elaiophylin and pimaricin) and the catalytic domains responsible for tetrahydropyran formation (apicularen).

Selected Publications
Boddy, C.N.; Hotta, K.; Tse, M.L.; Watts, R.E.; Khosla, C. Precursor-Directed Biosynthesis of Epothilone in Escherichia coli. J. Am. Chem. Soc. 2004, 126, 7436-7437.
Watanabe, K.; Wang, C.C.; Boddy, C.N.; Cane, D.E.; Khosla, C. Understanding Substrate Specificity of Polyketide Synthase Modules by Generating Hybrid Multimodular Synthases. J. Biol. Chem. 2003, 278, 42020-42026.
Boddy, C.N.; Schneider, T.; Hotta, K.; Walsh, C.T.; Khosla, C. Epothilone C Macrocyclization and Hydrolysis Are Catalyzed by the Isolated Thioesterase Domain of Epothilone Polyketide Synthase. J. Am. Chem. Soc. 2003, 125, 3428-3429.
Nicolaou, K.C.; Boddy, C.N.; Christopher, N.C. Atropselective Macrocyclization of Diaryl Ether Systems: Application to the Synthesis of Vancomycin. J. Am. Chem. Soc. 2002, 124, 10451-10455.
Offer J.; Boddy, C.N.; Dawson, P.E. Extending Synthetic Access to Proteins with a Removable Acyl Transfer Auxiliary. J. Am. Chem. Soc. 2002, 124, 4642-4646.
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