Regeneration of NAD ( P ) H Using Glucose G - Sulfate and Glucose - 6 - phosphate Dehydrogenase

Glucose 6-sulfate and glucose-6-phosphate dehydrogenase have been used for NAD(P)H cofactor regeneration in preparations of (Sfbenzyl-a-d1 alcohol and ,hreo-D"(+)-isocitrate (0.1-mol scale). The reduced nicotinamide cofactoN are more stable in solutions of glucose c-sulfate than in solutions of glucoee Gphosphate and thefu lifetimes in solution are correspondingly longer. The specific activities of the enzymes are, however, lower with glucose 6-sulfate than with glucose 6-phosphate. Glucose 6-sulfate appears to be a useful and piactical reducing agent for NADP; glucose G-phosphate is clearly superior for NAD. Comparisons of several methods for rnaking glucose o-phosphat€ indicate that phosphorylation of glucose with ATP (using ATP cofactor rccycling and hexokinase as catqlyst) i6 the most effective method for laboratory-scale syntheses.