利用功能基因组学方法研究酿酒酵母乙醇生物合成的调控机理

酿酒酵母在发酵生产乙醇的过程中存在的主要问题是前期高浓度底物葡萄糖的抑制和后期高浓度产物乙醇的抑制。功能基因组学技术的发展为从基因组水平上系统研究酿酒酵母乙醇生物合成的调控机理提供可能。本研究模拟工业发酵的条件，对酿酒酵母实验菌株BY4743为遗传背景的116个单基因缺失菌株进行了乙醇发酵试验，以发现基因和乙醇发酵的关系。结果表明乙醇对菌体得率系数高于平均值30%以上的基因缺失株有20株，其中高于50%以上基因缺失株有5株；低于平均值30%以上的基因缺失株有11株，其中低于45%以上的有5株。本研究为从整个酿酒酵母基因组水平上系统研究乙醇生物合成的调控机理建立了研究方法，提供了可行性验证。

Regulation Mechanism of Ethanol Biosynthesis in Saccharomyces cerevisiae through Functional Genomics Methodology

Inhibition of high sugar concentration in early stage and inhibition of high ethanol concentration in later stage are two major problems existing in the fermentation process to produce ethanol by Saccharomyces cerevisiae. The development of functional genomics technology has made it possible to study systematically the regulation mechanism of ethanol biosynthesis at genomic level. Industrial fermentation conditions was simulated in this study to carry out etha-nol fermentation experiments to discover relationship between genes and ethanol fermentation, taking 116 yeast single-gene deletion strains of BY4743 genetic background as ethanol experimental strains. The results showed that there were 20 gene-deletion strains with gain rate coefficient of ethanol to thalamus higher than 30% of the average, among them 5 gene-deletion strains were 50% higher; while those lower than 30% of the average were 11 strains, among them there were 5 strains being lower than 45%. This study has established research methods for regulation mecha-nisms at genomic level of S. cerevisae systematically to study ethanol biosynthesis as a whole, and provided feasibility tests and verifications.