摘要
目的:阿糖腺苷(Ara-A)是一种广谱抗病毒药物,临床上用于治疗多种病毒性疾病,同时也是合成阿糖腺苷单磷酸(Ara-AMP)的重要原料、本课题旨在寻找一种高效酶法生产嘌呤类阿糖核苷的方法。方法:以产气肠杆菌完整细胞为酶源,研究产气肠杆菌菌体培养条件对核苷磷酸化酶的影响及其诱导性。结果:胸苷磷酸化酶、尿苷磷酸化酶和嘌呤核苷磷酸化酶均可被多种核苷、核苷酸甚至碱基诱导。胞苷或胞苷酸的添加量为15-20mmol/L,诱导时间在0-8小时均可。经胞苷和胞苷酸诱导的菌体可使酶反应时间缩短6倍,大大提高了反应效率。经诱导的菌体,在反应后仍保持较高的核苷磷酸化酶活力:而未经诱导的菌体,一次反应后即丧失大量的酶活力。结论:核苷磷酸化酶的活性可以通过诱导而提高,以此优化阿糖腺苷的生产。
Objective： Ara-A is a broad spectrum antiviral medicine used to treat many viral disease. It is also used as key raw material for chemical synthesis of adenine arabinoside monophosphate （Ara-AMP）. In this paper, effect of culture conditions of Enterobacter aerogenes on NPase and the induction of NPase were studied. Methods： The synthesis of Ara-A was catalyzed by intact cells of Enterobacter aerogenes DGW-07. The influence and induction effect of medium ingredients on nucleoside phosphorylase were studied. Results. When the cells were cultured in the broth with 20 mmol/L cytidine added, the activities of uridine phosphorylase, thymidine phosphorylase and purine nucleoside phosphorylase increased 2.27, 4.75 and 1.77 times respectively. When cultured in the broth with 20mmol/L cytidine monophosphate added, the activities of uridine phosphorylase, thymidine phosphorylase and purine nucleoside phosphorylase increased 1.99, 4.25 and 1.63 times respectively. The optimal concentration of cytidine or cytidine monophosphate is 15-20 mmol/L, and the optimal induction time is from 0-8h. The reaction time catalyzed by cells induced by cytidine or cytidine acid was reduced by six times, so that the enzymatic efficiency was greatly improved. The cells induced can preserve most activity after enzyme reaction. However, the cells no induced lost most activity after one-time enzyme reaction. Conclusions. Enzyme activity of nucleoside phosphorylase can be improved by induction, and then the production of adenine arabinoside can be optimized.
出处
《现代生物医学进展》
CAS
2008年第2期255-258,279,共5页
Progress in Modern Biomedicine
基金
科技部中国科技型中小企业创新基金(07C26213100222)
关键词
产气肠杆菌
核苷磷酸化酶
诱导
阿糖腺苷
Enterobacter aerogenes
Nucleoside phosphorylase
Induction
Adenine arabinoside
