乙酰短杆菌酶法合成2′-脱氧鸟苷

Enzymatic Synthesis of 2′-Deoxyguanosine by Brevibacterium Acetylium

胸苷和鸟苷酸在乙酰短杆菌的核苷磷酸化酶和磷酸单酯酶作用下转化成鸟嘌呤、胸腺嘧啶、鸟苷和产物2′-脱氧鸟苷。通过考察菌体量、反应温度、反应pH值、底物浓度和磷酸盐浓度等参数,得到反应最适条件为20 mmol/L的胸苷和鸟苷酸,30 mmol/L的磷酸盐缓冲液(pH7.0),5%游离乙酰短杆菌在60℃下进行反应,经6 h胸苷转化率就可达到最高为56.4%。反应液通过离子交换的方法进行分离,可以得到纯度90.2%的2′-脱氧鸟苷。

Thymine,guanine,guanosine and the objective product,2′-deoxyguanosine,were enzymatically transferred from thymidine and guanosine monophosphate by nucleoside phosphorylase and phosphomonoesterase from Brevibacterium acetylium.By investigating the factors such as biomass,reaction temperature,reaction pH value,substrate concentration and phosphates concentration,optimum condition is 20mmol/L thymidine and guanosine monophosphate,30mmol/L phosphate buffer pH7 the 5% intact cell at 60℃,and 56.4% thymidine was biotransformed to 2′-deoxyguanosine for 6 hours.Ion exchange was used for the purification of 2′-deoxyguanosine from enzymatic reaction mixture,and its purity reached 90.2%.