摘要
优化了重组菌E.coli BL21(DE3)/pET28b(+)-NIT发酵产腈水解酶的条件,确定最适发酵培养基为:玉米浆粉25g.L-1,酵母浸出汁5g.L-1,NaCl 10g.L-1,Fe3+0.5mmol.L-1,初始pH值7.5;最适诱导产酶条件为:诱导剂乳糖0.5g.L-1,诱导剂加入时间为接种6h后,诱导温度30℃,诱导时间28h,在此条件下产酶量达到6161.46U.L-1。所得菌体用于不对称转化R,S-扁桃腈生成R-(-)-扁桃酸,转化率达92.02%,产物e.e.值达99%。
In this paper, culture conditions of recombinant E. coli BL21 （DE3）/pET28b （＋）-NIT producing nitrilase were optimized. The optimum culture medium was as follows.corn paste powder 25 g · L-1 ,yeast ex- tract paste 5 g · L-1 ,NaC1 10 g · L-1 ,Fe3＋ 0. 5 mmol · L-1 ,initial pH value 7.5.0.5 g · L-1 Lactose was added to the culture after inoculating 6 h. The highest nitrilase production reached 6161.46 U · L-1 after inducting for 28 h at 30 °C. The bioconversion of mandelonitrile by the recombinant nitrilase was also investigated. The result showed that the conversion rate of R-（-）-mandelic acid against substrate reached 92.02% with e.e. value of 99%.
出处
《化学与生物工程》
CAS
2012年第3期22-26,共5页
Chemistry & Bioengineering
基金
国家863计划资助项目(2009AA02Z203)
