摘要
为降低S-腺苷甲硫氨酸的生产成本,构建了同时表达腺苷激酶、腺苷酸激酶和乙酸激酶3 种酶的重组大肠杆菌菌株用于ATP 的合成,并对ATP 的转化条件进行了优化,优化后的反应体系为:腺苷30 mmol/L,乙酰磷酸二锂盐135 mmol/L,硫酸镁5 mmol/L,硼砂50 mmol/L,菌体2 g/L(湿重),反应液初始pH7.5,反应温度为35℃,反应时间为3 h,反应转化率可以达到99%以上。按照上述反应体系进行5 L 放大,反应结束后再投入65 mmol/L D,L-甲硫氨酸和50 g/L(湿重)表达腺苷甲硫氨酸合成酶的重组大肠杆菌菌体,并补加15 mmol/L 硫酸镁,转化18 h S-腺苷甲硫酸浓度能达到8.7 g/L,转化率达到72.5%。
In order to achieve ATP production as well as reduce the cost of producing S-adenosylmethionine,a recombinant Escherichia coli strain expressing adenosine kinase,adenylate kinase and acetate kinase simultaneously was constructed for ATP synthesis. The conditions of transforming ATP were optimized,and the optimized reaction system was as :adenosine 30 mmol/L,acetylphosphate dilithium 135 mmol/ L,magnesium sulfate 5 mmol/L,borax 50 mmol/L,E. coli strain 2 g/L(wet weight),initial pH 7.5,the reaction temperature 35 ℃, and reacting for 3 h,the conversion rate was over 99%. Based on the above result,the reaction system was enlarged in 5 L. After reaction ended,50 g/L(wet weight)recombinant E. coli strain expressing adenosylmethionine synthase,65 mmol/L D,L-methionine and 15 mmol/ L magnesium sulfate were added to the reaction system,the concentration of S-adenosylmethionine was up to 8.7 g/L and the conversion rate reached 72.5% after 18 h transformation.
作者
江林林
吴磊
许海霞
黄坚丽
张永进
徐期
杨勇
JIANG Lin-lin;YANG Yong;WU Lei;XU Hai-xia;HUANG Jian-li;ZHANG Yong-jin;XU Qi(Zhejiang Hisun Pharmaceutical Co. Ltd.)
出处
《生物技术通报》
CAS
CSCD
北大核心
2019年第6期221-226,共6页
Biotechnology Bulletin
