应用大肠杆菌的核苷磷酸化酶合成胸苷

Enzymatic Synthesis of Thymidine by Nucleoside Phosphorylases in Escherihia coli

摘要: 通过大肠杆菌核苷磷酸化酶的转脱氧核糖基作用，从胸腺嘧啶和２‘－脱氧核苷合成胸苷。优化了以ｄＵ为底物合成胸苷的反应条件。以３０ｍｍｏｌ／ＬｄＵ为底物其合成胸苷的转化率可达５．３％；以ｄＡ，ｄＣ，ｄＵ，ｄＧ的混合物为底物转化度为５２．６％；以ＤＮＡ降解后的２’－０脱氧核苷混合液作底物，反应液中胸苷浓度从９．２ｍｍｏｌ／Ｌ提高到１７．９ｍｍｏｌ／Ｌ。

Abstract: Deoxythymidine was synthesized by transdeoxyribosylation of thymine and 2'-deoxynecleosides using necleoside phosphorylase in E.coli.The condition of reaction was optimized.The yield of dT was 55.3% using dU as substrate,and 52.6% using a mixture of dA,dC,dU and dG. The conccntration of dT reached to 17.9mmol/L from 9.2mmol/L using a.mixture of 2'-deoxynucleosides as substrate resulting from enzymatic hydrolysis of DNA.