重组甘油单酯脂肪酶GMGL的高效表达及固定化  

High-efficiency Expression and Immobilization of Recombinant Monoglyceride Lipase GMGL

作　　者：牛亚春 蓝东明[2] 王永华[2] 杨博[1] NIU Ya-chun;LAN Dong-ming;WANG Yong-hua;YANG Bo(School of Biology and Biological Engineering,South China University of Technology,Guangzhou 510006,China;School of Food Science and Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学生物科学与工程学院,广东广州510006 [2]华南理工大学食品科学与工程学院,广东广州510640

出　　处：《现代食品科技》2021年第10期70-78,共9页Modern Food Science and Technology

基　　金：国家杰出青年科学基金资助项目(31725022)。

摘　　要：该研究以来源于海洋地衣芽孢杆菌的甘油单酯脂肪酶GMGL为研究对象,在5 L发酵罐中优化了重组大肠杆菌的发酵条件,确定了最佳诱导培养条件:诱导温度25℃,发酵培养基pH 7.0,发酵液菌体OD600达到20时添加IPTG至终浓度为1 mmol/L,葡萄糖流加方式为变速流加。诱导培养24 h,菌体湿重达到125.40 g/L,发酵液活力为1985 U/mL,较优化前(1185 U/mL)提高了67.50%。进一步对GMGL进行固定化研究,确定最佳固定化条件为:酶载量为100 mg/g,磷酸盐缓冲液离子强度为0.50 mol/L,pH为9,优化后固定化GMGL的活力为4770 U/g,较优化前(1650 U/g)提高了189.09%。利用扫描电镜(SEM)和傅里叶红外光谱(FT-IR)对固定化酶进行表征,证实GMGL成功负载在ECR8285上。上述结果表明将为高活力甘油单酯脂肪酶的高效制备提供了一定的研究依据。The monoglyceride lipase GMGL derived from Bacillus licheniformis was used as the research object.The fermentation conditions of recombinant Escherichia coli bacteria were optimized in a 5 L bioreactor,and the best inductive culture conditions were determined:inductive temperature 25℃,the pH of the fermentation mediumwas 7.0,the bacterial OD600 reached 20,and the final concentration of IPTG was 1 mmol/L.The glucose feeding method was variable speed feeding.After 24 hours of induction culture,the wet weight of the bacterial cell reached 125.40 g/L,and the fermentation activity was 1985 U/mL,which increasedby 67.5%compared to the pre-optimization period(1185 U/mL).Further immobilization studies were carried out on GMGL,and the optimal immobilization conditions were determined as follows:enzyme load was 100 mg/g,phosphate buffer salt concentration was 0.50 mol/L,and pH was 9.After optimization,the activity of immobilized GMGL was 4770 U/g,which increasedby 189.09%compared to that before optimization(1650 U/g).Using scanning electron microscopy(SEM)and Fourier infrared spectroscopy(FT-IR)for characterization,it was confirmed that GMGL was successfully loaded on ECR8285.These results will provide a research basis for the efficient preparation of monoglyceride lipase with high activity.

关 键 词：甘油单酯脂肪酶 发酵优化 固定化 

分 类 号：TQ925[轻工技术与工程—发酵工程]