α-氰基-3-苯氧基苄醇乙酸酯立体选择性水解酯酶产生菌的筛选及酶学特性初探

经过酵母菌富集培养,以α-氰基-3-苯氧基苄醇乙酸酯为唯一碳源培养和分离,并进一步用手性HPLC法复筛,得到了两株优先立体选择性水解(S)-α-氰基-3-苯氧基苄醇乙酸酯的酵母菌菌株S11和S25。两株酵母菌均能产生耐酸酯酶,在pH 3.0时对α-氰基-3-苯氧基苄醇乙酸酯进行立体选择性水解,产物对映体过量值(ee/em>p)均在95％以上,转化率(C)分别达50％和46％。测定了菌株S11的生长曲线,并对其产酶特性进行了初探,发现其所产酶为生长偶联型的胞内酶。

Study and Screening of Esterase Producer for Hydrolyzing α-Cyano-3-phenoxybenzyl Acetate with High Enantioselectivity

Culture and separation was made by using α-cyano-3-phenoxybenzyl acetate as the only carbon source after yeast enrichment. Further screening was performed by chiral HPLC analysis. Two yeast strains (S11 and S25) producing esterase with high enantioselectivity and conversion were isolated. Esterases were stable and remained activity at pH 3.0. Enantiomeric excess of (S)-α-cyano-3-phenoxybenzyl alcohol both reached 95%, the conversion of substrate reached 50% and 46% , respectively. The process of growth and partial enzymatic properties of S11 was investigated. Experiments demonstrated that it was a membrane-associated enzyme found in the cell debris.