摘要
为了实现来源于嗜热栖热菌的海藻糖合酶的高效表达,对E.coli BL21(DE3)/p ET24a(+)-Tre S基因工程菌在3 L发酵罐进行了发酵工艺优化,获得的最优发酵条件为:诱导温度32℃,当OD600达到50时以0.2 g/(L·h)的速率补加乳糖进行诱导产酶,在该条件下发酵35 h时酶活达到472 U/m L,是优化前的2.3倍;进而采用该条件在30 L发酵罐进行了初步放大研究,酶活达到356 U/m L。由于该海藻糖合酶热稳定性好,因此尝试了高温处理破碎E.coli细胞以释放海藻糖合酶,结果表明,80℃处理30 min,海藻糖合酶的得率可达72.3%,具有工业化应用前景。
In order to achieve efficient production of the trehalose synthase from Thermus thermophilus ,thQ optimization of fermentation conditions was investigated in E.coli BL21 (DE3) harboring the plasmid pET24a(+)-TreS. The optimized fermentation conditions were as follows:the inducing temperature is 32 ℃ ,the adding rate of lactose is 0.2 g/(L·h) When OD600 reached 50. Under the condition,the enzyme activity reached 472 U/mL at cultivation of 35 h,was 2.3 times than before. In addition,the fermentation was performed in 30 L bioreactor under the condition of preceding narrative,the enzyme activity reached 356 U/mL. Because the thermal stability of trehalose synthase is good, E.coli cell was broken up through high temperature. The results showed that treated it 30 min under 80℃ the yield of trehalose synthase reached 72.3%. It have industrial application prospect.
出处
《食品与生物技术学报》
CAS
CSCD
北大核心
2016年第9期913-919,共7页
Journal of Food Science and Biotechnology
基金
国家自然科学基金杰出青年基金项目(31425020)
关键词
海藻糖合酶
高效表达
基因工程菌
发酵罐
高温处理
trehalose synthase, high-efficiency expression, genetically engineered bacterium, fermentor, high-temperature processing