产β-苯丙氨酸变位酶基因工程菌的构建及其发酵条件优化

发布时间：2019-05-14 12:26

【摘要】：构建β-苯丙氨酸变位酶基因表达重组质粒pET-28apam,并转化大肠杆菌BL21,获得β-苯丙氨酸变位酶基因重组菌。考察培养基初始pH、摇床转速、种龄、发酵时间以及装液量5个因素对β-苯丙氨酸变位酶基因工程菌产酶活性的影响,确定较佳发酵条件为:培养基初始pH 7.0、摇床转速200r/min、发酵时间24h、装液量50mL/500mL、种龄10h。采用Box-Behnken试验设计,选择了种龄、初始pH、发酵时间3个对β-苯丙氨酸变位酶活力影响较大的因素进行响应面优化。优化结果为:在种龄12.8h、初始pH 6.7、发酵时间25.2h条件下,PAM活力达到11.15 U/mL,比优化前酶活4.87U/mL提高了128.9%。
[Abstract]:The recombinant plasmid pET-28apam, was constructed and transformed into E. coli BL21, to obtain the recombinant strain of 尾-phenylalanine translocation gene. The effects of initial pH, shaking speed, seed age, fermentation time and liquid loading on the enzyme production activity of 尾-phenylalanine translocation genetic engineering bacteria were investigated. The optimum fermentation conditions were as follows: the initial pH 7.0, The rotating speed of shaking table was 200 r / min, the fermentation time was 24 h, the amount of liquid was 50 mL / 500 mL, and the seed age was 10 h. Using Box-Behnken design, three factors, seed age and initial pH, fermentation time, which had great influence on the activity of 尾-phenylalanine translocation enzyme, were selected to optimize the response surface. The results showed that under the conditions of seed age 12.8 h, initial pH 6.7 and fermentation time 25.2 h, the activity of PAM reached 11.15 U / mL, which was 128.9% higher than that before optimization.
【作者单位】：安徽工程大学生物与化学工程学院;
【基金】：国家自然科学基金面上项目(编号:31671797) 安徽省高等学校省级自然科学研究重点项目(编号:KJ2016A801) 国家级大学生创新创业训练计划项目(编号:201510363072)
【分类号】：TS201.3

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