论文部分内容阅读
采取研磨、离心分离、多层过滤和丙酮沉析等步骤,从红豆中提取具有不对称还原芳香酮能力的羰基还原酶(CR),经快速分离纯化获得了纯化倍数为5.8倍的红豆源CRrb酶液,考察了其酶学特性,与微生物源CR的酶学特性进行比较,将CRrb与甲酸脱氢酶(FDH)耦合构建CRrb/FDH双酶体系连续催化β-羟基苯乙酮制备(R)-苯基乙二醇.结果表明,源于红豆的CRrb最适反应pH值为6.0,最适反应温度为45℃,在40～60℃范围内耐热性好于一般微生物源CR.CRrb的米氏常数Km=5.68 mmol/L,最大反应速率Vmax=20.21μmol/(min·m L),对底物的亲和力和催化效率比微生物源CR好.底物较佳耐受浓度为60 mmol/L,较微生物源的CR高.CRrb/FDH酶活比为1:1.5时耦合体系反应效率最佳,批次反应转化1 mol辅酶可获得产物的量由266 mol提高到365 mol.
The steps of grinding, centrifugation, multi-layer filtration and acetone precipitation were used to extract carbonyl reductase (CR) with the ability to asymmetrically reduce aromatic ketones. The purified CRrb Enzymatic activity was investigated, and its enzymatic properties were compared with those of microbial origin CR. CRrb was coupled with formic acid dehydrogenase (FDH) to construct a two-enzyme system of CRrb / FDH. ) -phenylglycol.The results showed that the optimum pH of CRrb derived from red beans was 6.0 and the optimum reaction temperature was 45 ℃, and the heat resistance of CRrb from red bean was better than that of common microbial source CR.CRrb (Km = 5.68 mmol / L) and the maximum reaction rate Vmax = 20.21μmol / (min · m L), the affinity and catalytic efficiency of the substrate was better than that of microbial origin CR.The best substrate tolerance was 60 mmol / L, which is higher than that of microbial sources.The reaction efficiency of the coupling system is the best when the ratio of CRrb / FDH is 1: 1.5, and the amount of product obtained from batch reaction of 1 mol coenzyme is increased from 266 mol to 365 mol.