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研究了产核苷磷酸化酶大肠杆菌的摇瓶培养和发酵罐培养特征以及乙酸盐和底物诱导对核苷磷酸化酶活力的影响。结果表明：摇瓶培养时，延长菌体培养时间，菌体部分自溶时酶的转化率最高；发酵培养基中加入１０ｇ／Ｌ乙酸钠可使底物转化率提高７．７％，０．００１ｇ／Ｌ的底物ｄＵ诱导可使酶活力提高１１．０％；流加底物ｄＵ对酶反应转化率无显著影响，表明该酶促反应为非２′－脱氧尿苷底物抑制型；反应过程存在扩散控制，酶反应的最佳摇床转速为１６０ｒ／ｍｉｎ。
The characteristics of shake flask culture and fermenter culture of nucleoside phosphorylase-producing Escherichia coli and the effect of acetate and substrate induction on nucleoside phosphorylase activity were studied. The results showed that when the flask was cultured, the conversion rate of the enzyme was prolonged when the cells were cultured and the autolysis of the cells was partial. The addition of 10g / L sodium acetate in the fermentation medium could increase the substrate conversion rate by 7.7%. Under the induction of substrate dU of 001g / L, the enzyme activity increased by 11.0%. The addition of substrate dU had no significant effect on the conversion of enzyme reaction, indicating that the enzymatic reaction was a non-2’-deoxyuridine substrate inhibitor. There is diffusion control in the reaction process, and the best shaking speed of enzyme reaction is 160r / min.