丙酸梭菌静息细胞法生物合成丙烯酸

Biosynthesis of acrylic acid by resting cells of Clostridium propionicum

介绍了丙烯酸生物合成的途径并比较了以不同起始物生物合成丙烯酸的特点。建立了以丙酸为底物的静息细胞生物合成丙烯酸的方法,并优化了生物转化工艺参数,其最优值分别为pH8.5、温度42℃、底物浓度250 mmol/,L、电子受体亚甲基蓝浓度0.2%～0.3%、促进剂L-丙氨酸浓度为20 mmol/L、Zn^(2+)离子浓度为1 mmol/L。通过紫外和硫酸二乙酯复合诱变筛选到一株能耐受丙烯酸浓度为40 mmol/L的突变株,以其静息细胞转化丙酸能获得25.2 mmol/L丙烯酸。

The metabolic pathway for biosynthesis of acrylic acid was introduced and the characteristics of different initial substrates for biosynthesis of acrylic acid were compared. The method for biosynthesis of acrylic acid by resting cell with propionate as substrate was established, and then the biotransformation parameters were optimized. The optimum values of pH, temperature, concentrations of substrate, electron acceptor （methylene blue）, accelerator （L-alanine） and Zn2＋ were 8.5, 42℃, 250 mmol/L, 0.2% - 0.3%, 20 mmol/L and 1 mmol/L, respectively. An acrylate-tolerating mutant, which could tolerate 40 mmol/L acrylic acid, was isolated by combined mutation with UV and diethyl sulfate. By using the resting cells of acrylate-tolerating mutant, 25.2 mmol/L of acrylic acid were obtained.