Kuroda H, Miyadera A, Imura A, Suzuki A
Chem Pharm Bull (Tokyo). 1989 Nov;37(11):2929-32. doi: 10.1248/cpb.37.2929.
Debenzylating enzyme from Aspergillus niger enzyme (commercial crude cellulase) catalyzes the hydrolysis of cetraxate benzyl ester hydrochloride (2), a precursor of the antiulcer agent (1). The enzyme was highly purified by three kinds of chromatographies (hydrophobic, ion exchange, gel filtration) with a recovery of 36%. The content of the debenzylating enzyme was about 0.1% in the crude cellulase, but the enzyme showed no cellulase activity. The purified enzyme was inactivated by Hg2+, and diisopropyl phosphorofluoridate (DFP). It was a monomer with a molecular weight of about 35,000, and its isoelectric point was estimated to be 5.3. It showed a debenzylating activity for the phenylpropionic acid benzyl ester moiety of various benzyl ester derivatives, and the benzyl ester of phenylalanine or that of tyrosine was also well hydrolyzed.
来自黑曲霉的脱苄基酶（市售粗纤维素酶）催化抗溃疡剂（1）的前体盐酸西曲酸苄酯（2）的水解。通过三种色谱法（疏水色谱、离子交换色谱、凝胶过滤色谱）对该酶进行了高度纯化，回收率为36%。粗纤维素酶中脱苄基酶的含量约为0.1%，但该酶没有纤维素酶活性。纯化后的酶被Hg2+和二异丙基氟磷酸酯（DFP）灭活。它是一种分子量约为35000的单体，其等电点估计为5.3。它对各种苄酯衍生物的苯丙酸苄酯部分表现出脱苄基活性，苯丙氨酸苄酯或酪氨酸苄酯也能被很好地水解。
