一株产D-海因酶菌株的鉴定及离子束诱变选育  

Identification of A B. megaterium Producing D-Hydantoinase and Its Mutation Breeding by Ion Implantation

作　　者：董妍玲[1] 唐瑞[1] 潘学武[2] 

机构地区：[1]武汉生物工程学院生物技术系,武汉430415 [2]武汉大学资源与环境科学学院环境科学系,湖北武汉430079

出　　处：《氨基酸和生物资源》2010年第2期1-5,10,共6页Amino Acids & Biotic Resources

基　　金：武汉市教育局重点项目(200715)

摘　　要：首次报道了产D-海因酶的巨大芽孢杆菌,通过对该菌进行离子束诱变,获得酶活最高增加3倍的突变株M5,对M5的产酶条件进行优化,得到最佳的发酵条件为玉米浆1.5%,葡萄糖1%,油酸1.5%,氯化钠0.5%,并添加50 mg.L-1的Mn2+、Zn2+及500 mg.L-1的Mg2+,pH8.0,30℃发酵24 h,酶活力可达到每毫升2.119 U,比优化前突变株提高了300%,比出发菌株提高了850%。A D - Hydantoinase producing strain of B. megaterium was identified by its 16s rRNA gene sequence analysis for the first time. Mutants producing higher enzyme activity were obtained by nitrogen ion implantation. The culture medium and the fermentation conditions of the mutants were optimized by orthogonal experiment based on the former culture medium and fermentation conditions. The result showed that the best medium composition was as the following： corn steep liquor of 1.5 %, glucose of 1%, fatty acid of 1.5 %, NaCl of 0.5 %, 50 μg· mL^- 1 of Mn2 ＋ and Zn2 ＋ and 500 μg· mL^- 1 Mg2 ＋ , initial pH of 8.0. When cultured for 24 hours at 30 ℃, the mutant M5 had the highest enzyme activity as 2. 119 U · mL^-1 , which enhanced 300% than that in the former medium and 850% than the starting strain.

关 键 词：巨大芽孢杆菌 D-海因酶 16s RRNA 离子注入 发酵条件 

分 类 号：Q936[生物学—微生物学]