Diastereoselective Enzymatic Aldol Additions: L-Rhamnulose and L-Fuculose 1-Phosphate Aldolases from E. coli


  • Enzymes in Organic Synthesis, part 1. This research was supported by the Deutsche Forschungsgemeinschaft (Grant Fe 244/2-l), the Wissenschaftliche Gesellschaft Freiburg, and the Fonds der Chemischen Industrie and the Comisión Asesora de Investigación Cientifica y Técnica (Grant PB 85-0084). We gratefully acknowledge the generous gift of bacterial strains and plasmid DNA harboring the fuc genes by Prof. Dr. E. C. C. Lin and Dr. Y-M. Chen of Harvard Medical School, Boston, and a preprint of ref. [8] obtained from Dr. A. Ozaki.


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Two bacterial aldolases, RhuA and FucA, which are readily accessible by overex-pression, catalyze the asymmetric addition of dihydroxyacetone phosphate to various aldehydes. The high degree of enantio-and diastereoselectivity for the L-threo (RhuA) and D-erythro (FucA) stereochemistry of the products and the high stability of the enzymes make it possible to prepare rare carbohydrates and their derivatives as well as other polyhydroxylated compounds.