重组枯草芽孢杆菌PaE菌株的构建及碳代谢阻遏效应研究

通过基因重组的方法，将枯草芽孢杆菌168的α-淀粉酶基因amyE（除掉启动子）整合在Paxo1质粒上，然后将重组表达质粒Paxo1-amyE导入枯草芽孢杆菌168菌株基因组中的半乳糖苷酶基因lacZ位点。通过转化筛选和重组基因分析，获得含有重组α-淀粉酶基因的工程菌株PaE。经过添加4 种不同的碳源发酵实验检测，在外加2 g/100 mL木糖诱导的情况下，重组菌株的α-淀粉酶产量均有增加。而且重组菌株在一定程度上能够克服葡萄糖等还原性糖引起的碳代谢阻遏现象，提高了α-淀粉酶产量。

Construction and Carbon Catabolite Repression of Recombinant Bacillus subtilis PaE

Using gene recombination method, the alpha amylase gene amyE (without promoter) of Bacillus subtilis was
integrated into Paxo1 plasmid and the galactosidase gene lacZ of B. subtilis strain 168 was introduced into the recombinant
expression plasmid Paxo1-amyE. After transformation and screening analysis, genetically engineered strain PaE containing
the recombinant alpha amylase gene was selected. With the addition of four different carbon sources, the alpha amylase
production by the recombinant strain was promoted under the induction of 2 g/100 mL xylose. In addition, the recombinant
strain could overcome the carbon catabolic repression caused by reducing saccharides such as glucose to a certain extent to
improve the yield of alpha amylase.