3] Coimmobilized system of NAD with dehydrogenases

Abstract

Publisher Summary This chapter outlines the preparation of the coimmobilized gels of nicotinamide adenine dinucleotide (NAD) and dehydrogenases and their application to bioreactors for synthesis and analysis. The solid-phase coimmobilization of NAD and a dehydrogenase and the covalent binding of an NAD derivative in or near the active site of dehydrogenases have also been reported in the chapter. The recycling of NAD is a prerequisite for the industrial application of dehydrogenases. The most effective way of realizing this is to maintain both NAD and the coupled dehydrogenases in one reactor system (bioreactor) and recycle NAD in situ. The activities of the immobilized dehydrogenases were assayed in the chapter by the flow method using a substrate solution of the same composition as in the standard assay procedure. The apparatus consisted of a test tube held in a water bath (30°) and a flow system with a flow cuvette in the spectrophotometer and a peristaltic pump. A net was attached at the inlet of the flow system to filter the gels.