苯酚羟化酶基因工程菌转化4-乙烯基苯酚特性研究

Biotransformation of 4-Vinylphenol by Gene Engineered Strain PH_(_IND)

4-乙烯基苯酚广泛用作食品的调味剂及聚4-乙烯基苯酚类聚合物等的合成。近年来,研究发现4-乙烯基苯酚是苯乙烯在小鼠和人体中的次要代谢物,具有肝毒性和呼吸毒性。因此,利用生物定向转化技术降低4-乙烯基苯酚的毒性将具有实际意义。文章考察了含苯酚羟化酶基因的工程菌PH_IND生物转化4-乙烯基苯酚的条件,确定其最优条件为:菌株PH_IND的OD600为2.5,4-乙烯基苯酚的浓度为1 mmol/L,葡萄糖浓度为20 mmol/L,缓冲溶液的pH为8。在该条件下,生物转化呈一级动力学趋势,反应180 min后,转化率为31%。分子对接结果表明,4-乙烯基苯酚可以和苯酚羟化酶大亚基的活性位点结合,液相色谱-质谱联用分析结果表明4-乙烯基苯酚被转化为4-乙烯基儿茶酚。

4-vinylphenol,which is widely used in the synthesis of condiments,polymers and resins,has been paid many attentions due to its hepatotoxic and pneumotoxic effects to organisms as the metabolite of styrene in rats and human.Using biotransformation technology to decrease 4-vinylphenol toxicity will be of practical significance.Current studies investigated the biotransformation conditions of 4-vinylphenol by strain PH_IND,and the optimal conditions were as OD600 of PH_IND 2.5,4-vinylphenol concentration 1 mmol/L,pH 8 and glucose concentration 20 mmol/L.Under the optimal conditions,the biotransformation obeyed the first-order kinetics,and transformation rate reached approximately 31% after 180 min.Molecular docking indicated that 4-vinylphenol could interact with the active site of alpha-subunit of the phenol hydroxylase and LC-MS analysis demonstrated that 4-vinylphenol could be transformed to 4-vinylcatechol by strain PH_IND.