高分子化補酵素の合成とその酵素リアクタ-への応用 Macromolecular derivatives of NAD(P) and their application in model enzyme reactors.
1. An NAD derivative carrying a vinyl group was copolymerized with acrylamide or methacrylamide, and various water-soluble macromolecular NAD derivatives (polymeric NAD derivatives) were obtained. I investigated the coenzymic properties of the polymeric NAD derivatives and concluded that smaller NAD derivatives and lower NAD contents in the polymer chain had higher cofactor activity.2. Poly(ethylene glycol)-bound NAD (PEG-NAD) was prepared by coupling N^6-(2-carboxyethyl)-NAD to one termial of α, ω-diaminopoly(etylene glycol) with water-soluble carbodiimide. The kinetic properties of NAD(H), N^6-(2-carboxyethyl)-NAD(H) and PEG-NAD(H) were investigated with various dehydrogenases from different sources.3. NADP derivatives alkylated at the 2'-phosphate and/or 6-amino groups of the adenosyl moiety were prepared, and the effects of these modifications of NADP on its cofactor activity for various dehydrogenases were investigated. Then, poly(ethylene glycol)-bound NADP (PEG-NADP) was prepared by selective alkylation of the 6-amino group of NAD. PEG-NADP has good cofactor activity for some dehydrogenases but not for isocitrate or glucose dehydrogenases.4. The kinetic properties of a continuous enzyme reactor containing rabbit muscle lactate dehydrogenase, horse liver alcohol dehydrogenase, and PEG-NAD were investigated experimentally and theoretically. The steady-state behavior of the enzyme reactor was explained semi-quantitatively by a simple kinetic model. The operational stability of a continuous enzyme reactor containing PEG-NAD and thermostable dehydrogenases was also studied.
醗酵工学会誌 64(2), p77-97, 1986-03