产腈水解酶菌株的诱变及培养优化

Mutation and cultivation of Rhodococcus rhodochrous to improve nitrilase productivity

对实验室保存的1株产腈水解酶的Rhodococcus rhodochrous菌株采用氯化锂进行诱变处理,筛选得到了1株产酶活力较高的菌株tg1-A6。经过优化得到培养基的配方为(g.L-1):葡萄糖10,谷氨酸钠10,酵母膏3,己内酰胺7,MgSO40.5,K2HPO40.75,KH2PO40.75。当培养温度28℃,摇床转速200 r.min-1,初始pH值7.0,通过补加葡萄糖,该菌的腈水解酶酶活可达到26.77 U.mL-1。

To improve the nitrilase production, a strain of Rhodococcus rhodochrous was treated with UV radiation and LiCl, a mutant, tgl-A6, with higher nitrilase activity was obtained. Optimized with the method of orthogonal test , the component （g· L^-1） of culture medium was glucose 10, glutamine 10, yeast extract 3, caprolactam 7, MgSO40. 5, K2HPO4 0. 75, KH2PO4 0. 75. Under the cultural conditions of initial pH 7.0, cultural temperature 28℃, agitation rate 200 r·min^-1 and supplement of glucose, the nitrilase activity of Rhodococcus rhodochrous tgl-A6 reached 26. 77 U· mL^-1.