乙醇脱氢酶过表达对醋酸菌发酵产酸影响研究

The production of acetic acid by Acetobacter pasteurianus with enhanced expression of alchol dehydrogenase

目的:通过构建乙醇脱氢酶过表达基因工程菌株提高醋酸菌醋酸发酵产率。方法:PCR扩增沪酿1.01 Acetobacter pasteurianus CICC20001的乙醇脱氢酶亚基I(Alcohol dehydrogenase I,adh A)和乙醇脱氢酶亚基II(Cytochrome c subunit,adh B)基因,将其依次连接到质粒pBBR1MCS-4中,构建重组质粒pBBR-adh A-adh B,并将该重组质粒导入沪酿1.01,成功获得过表达乙醇脱氢酶的基因工程菌,并对基因工程菌与原始菌的微观形态以及发酵特性进行对比分析。结果:乙醇脱氢酶过表达基因工程菌的醋酸发酵产率和酒精耐受性都有所提高。结论:乙醇脱氢酶的过表达不仅提高了醋酸菌的产酸率,其酒精耐受性也有显著提高。

Objective： The production of acetic acid was raised by constructing an engineered strain with high-expressed alchol dehydrogenase（ADH）.Methods： Genes adh A and adh B of Acetobacter pasteurianus CICC20001 which coding the subunit I and subunit II of alcohol dehydrogenase were amplified by PCR,and linked with vector to get the plasmid vector p BBR-adh A-adh B.Then the engineered strain was obtained through inserting the plasmid into Acetobacter pasteurianus CICC20001.And the micromorphology and fermentation characteristics of the engineered strain and original strain were contrasted and analyzed,respectively.Results： The production of acetic acid and the tolerance of ethanol by fermentation of engineered strain were both improved.Conclusion： The enhanced expression of ADH can not only increase acetic acid yield but also improve the tolerance of ethanol significantly.