金属离子对卤醇脱卤酶发酵生产的影响

在以基因工程大肠杆菌为生产菌发酵生产卤醇脱卤酶过程中,某些金属离子对卤醇脱卤的生产有较大的影响。首先,通过单因子实验确定几种典型微量元素的最佳产酶浓度,其次,通过2水平析因实验和最陡爬坡实验确定了显著影响因子及其浓度拐点,其分别是ZnSO4.7H2O、CoCl2.6H2O和FeSO4.7H2O。最后,运用响应面分析法确定了微量元素的最佳配比为FeSO4.7H2O 11.86g/L,ZnSO4.7H2O 2.0g/L,MnSO4.H2O 1.0g/L,CaCl20.05g/L,CoCl2.6H2O 1.2g/L,CuSO4.5H2O 0.8g/L。与对照生产水平相比,当添加最佳配比金属离子到培养基中后,酶活提高了2倍。

Effects of metal ions on production of the halogen alcohol dehalogenase

Some metal ions have great effects on production of the halogen alcohol dehalogenase by fermentation with recombinant E.coli.Firstly,optimal concentrations of some typical trace elements were obtained through the single factor experiments.Secondly,significant factors and their inflection points were determined by the two-level factorial experiments and steepest ascent experiments.The significant factors are ZnSO4·7H2O,CoCl2·6H2O and FeSO4·7H2O.Finally,Response surface methodology was utilized to determine the optimal ratio of the trace elements,which were FeSO4·7H2O 11.86g/L,ZnSO4·7H2O 2g/L,MnSO4·H2O 1g/L,CaCl2 0.05g/L,CoCl2·6H2O 1.2g/L,CuSO4·5H2O 0.8g/L,respectively.Compared with the control,the enzyme activity increased by 2-fold when the optimal ratio metal ions were added to the medium.