重组大肠杆菌生产硫磺矿硫化叶菌β-半乳糖苷酶发酵条件初步研究  

Preliminary study on optimization ofβ-galactosidase production by recombinant E.coli

作　　者：吴玉飞[1,2,3] 钱磊[1] 张帆[1,2,3] 陈晟[1,2] 吴敬[1,2] 

机构地区：[1]食品科学与技术国家重点实验室江南大学,无锡214122 [2]工业生物技术教育部重点实验室,无锡214122 [3]江南大学生物工程学院,无锡214122

出　　处：《工业微生物》2012年第6期47-52,共6页Industrial Microbiology

基　　金：食品科学与技术国家重点实验室科研基金(SKLF-MB-200802)

摘　　要：为了实现来源于S.solfataricus的β-半乳糖苷酶的高效表达,对E.coli BL21(DE3)/pT7-7-lacS基因工程菌的发酵培养基进行优化,获得最优的发酵培养基为:甘油浓度为10 g/L,蛋白胨浓度为18 g/L,酵母膏浓度为18g/L,磷酸盐浓度为15 mmol/L,Mg^(2+)离子浓度为5 mmol/L,乳糖诱导浓度为5 g/L。在优化条件下,β-半乳糖苷酶的酶活由初始的43.0 U/mL提高到83.4 U/mL。在此基础上,在3 L发酵罐上进行了初步放大,于DD_(600) 50时开始流加乳糖诱导,最终酶活达172.4U/mL,为摇瓶水平的2倍,为β-半乳糖苷酶的工业化生产奠定基础。In order to achieve high production ofβ-galactosidase （LACS）, the optimization of culture medium was investigated in E. coli BI21 （ DE3 ） harboring the plasmid pT7-7-lacS. The optimized medium were as follows ： 5 g/L glycerol, 18 g/L peptone, 18 g/L yeast extract, 5 mmol/L Mg2＋ , 15 mmol/L PO43- , 5 g/L lactose as inductor. Under the optimized conditions, the enzyme activity increased from 43.0 U/mL to 83.4 U/mL. In addition, the fermentation of recombinant E. coli was performed in 3 L bioreactor. When OD600 reached 50, lactose was added as inductor and the highest activity reached 172.4 U/mL, which was twice as high as that in flask.

关 键 词：Β-半乳糖苷酶 重组大肠杆菌 发酵优化 

分 类 号：TQ925[轻工技术与工程—发酵工程]