产海因酶的菌种筛选和产酶条件的研究

利用5-苄海因作为唯一氮源法筛选高产海因酶的菌种，从本实验室保存的221株菌种中筛选出12株具有不对称水解5-苄海因生成N-氨甲酰基-苯丙氨酸的菌株，其中假单胞菌（Pseudomonassp.)X4-49具有较高的产酶活力，对此菌的产酶条件的研究表明，产酶的最佳碳源为甘油，最佳氮源为蛋白胨，最佳诱导物为苄海因，尿嘧啶，苄海因作为诱导物的有效浓度为0.2%，产酶的最适培养基的初始pH为7.0。培养条件为33℃，13h。

Screening of strains producing hydantoinase and their enzyme production conditions

A screening method was developed in which 5-benzylhydantoin was used as the sole carbon source. 12 strains were screened from 221 bacteria strains that could catalyzed hydrolysis of 5-benzylhydantoin to produce N-carbamyl-D-phenylalanine, while Pseudomonas sp. X-49 possessed higher enzymatic activity. The study on the enzyme production illustrated that the optimal carbon source and nitrogen source were glycerol and peptone, respectively. The optimal indue-er was benzylhydantoin at 0. 2 % . The optimal initial pH of the media was 7.0. The highest enzyme activity was obtained at 331 incubating for 13 hours. It was found that the optimal substrate was benzylhydantoin at pH8.0-8.5 and 35! .