Crystallization and preliminary X-ray analysis of a NADPH 2-ketopropyl-coenzyme M oxidoreductase/carboxylase

NADPH 2-ketopropyl-coenzyme M (2-mercaptoethanesulfonate) oxidoreductase/ca rboxylase is the terminal enzyme in a metabolic pathway that results in the conversion of propylene to the central metabolite acetoacetate. This enzym e is an FAD-containing enzyme that is a member of the NADPH:disulfide oxido reductase family of enzymes and catalyzes the cleavage and carboxylation of 2-ketopropyl-coenzyme M to form acetoacetate and coenzyme M. Crystallizati on trials have revealed that the highest diffraction quality crystals (bett er that 2.0 Angstrom resolution) could be achieved when the substrate or pr oduct of the reaction was added to the enzyme in a stoichiometric excess.