木糖和葡萄糖共发酵生产L-组氨酸  

Co-fermentation of xylose and glucose for L-histidine production

作　　者：吴鹤云 张悦[1] 蒋帅 田道光 谢希贤[1,2] 陈宁 WU Heyun;ZHANG Yue;JIANG Shuai;TIAN Daoguang;XIE Xixian;CHEN Ning(College of Biotechnology,Tianjin University of Science and Technology,Tianjin 300457,China;National and Local United Engineering Lab of Metabolic Control Fermentation Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学生物工程学院,天津300457 [2]代谢控制发酵技术国家地方联合工程实验室,天津300457

出　　处：《食品与发酵工业》2020年第16期115-120,共6页Food and Fermentation Industries

基　　金：国家重点研发计划(2018YFA0900300)。

摘　　要：以1株L-组氨酸生产菌Escherichia coli HIS1为研究对象,优化其L-组氨酸合成关键酶His G*的诱导条件。通过摇瓶发酵的方式确定诱导剂木糖的最适质量浓度为10 g/L;通过5 L发酵罐发酵的方式确定最佳诱导时间为发酵8 h时诱导;因发酵过程中木糖会被消耗,故通过多次添加木糖或敲除xyl A基因阻断木糖代谢途径保持发酵液中的木糖浓度,以稳定诱导条件。结果表明,木糖同时作为诱导剂和碳源更有利于L-组氨酸的发酵生产,为此摸索出了木糖和葡萄糖共发酵生产L-组氨酸的发酵工艺。该工艺主要控制要点为发酵8 h之后添加质量浓度为10 g/L的木糖,发酵过程中流加木糖和葡萄糖质量比为1∶5的糖溶液。最终L-组氨酸的产量可达56.5 g/L,是纯葡萄糖发酵时的2倍。Taking an L-histidine-producing strain Escherichia coli HIS1 as research object,the induction conditions of key enzyme HisG* for L-histidine synthesis were optimized. The optimal concentration of xylose was determined to be 10 g/L by shake flask fermentation and the optimal induction time was determined to be 8 h in a 5 L fermenter. Since xylose was gradually consumed during the fermentation,adding xylose multiple times or knocking out xylA gene to block xylose metabolism pathway was carried out to maintain xylose concentration and stabilize the induction conditions. The results showed that xylose was more conducive to L-histidine fermentation as both inducer and carbon source.To this end,process for L-histidine production by co-fermentation of xylose and glucose was proposed.The main control point of this process was to add 10 g/L xylose after fermentation for 8 h and a mixed solution was supplemented during the fermentation,of which the mass ratio of xylose and glucose was 1∶5. The final L-histidine production was 56. 5 g/L,as twice as that of pure glucose fermentation.

关 键 词：L-组氨酸 发酵优化 木糖诱导 混合碳源 大肠杆菌 

分 类 号：TQ922[轻工技术与工程—发酵工程]