中文摘要：

蔗糖基生物质是热带和亚热带地区重要的生物质材料,因而在微生物发酵和微生物代谢原料中具有重要的地位。酿酒酵母（Saccharomyces cerevisiae）具有以蔗糖为原料进行代谢的能力,在酿酒酵母的基因组中蔗糖水解酶基因共有6个结构基因。本研究以酿酒酵母INVSC1为出发菌株,首先利用基因敲除技术构建suc2基因缺失菌株,然后将suc2基因回补,从而研究suc2基因对酿酒酵母蔗糖关键代谢途径及蔗糖代谢特性的影响。以蔗糖为碳源的发酵培养基中,在静置条件下发酵,suc2基因缺失菌株失去了利用蔗糖代谢的能力,回补菌株则恢复了对蔗糖的代谢;而且回补菌株对蔗糖的利用率及乙醇产量均比出发菌株有所提高。suc2基因是酿酒酵母蔗糖代谢的关键基因,对蔗糖的代谢具有决定性作用,可以作为蔗糖代谢途径改造的一个关键点。

英文摘要：

Sucrose-based biomass is an important biomass in tropical and subtropical regions,thus it has an important position in the feedstock of microbial fermentation and microbial metabolism. Saccharomyces cerevisiae has the metabolize ability to sucrose based raw material. It was found that there were six structural genes encoded sucrose hydrolyze enzyme in Saccharomyces cerevisiae genome. In this study,Saccharomyces cerevisiae INVSC1 was used as starting strain. First of all,suc2 gene deletion strain was constructed by gene knockout technology.Then,suc2 gene was complemented. Finally,effects of suc2 gene on sucrose key metabolic pathways and metabolic properties in Saccharomyces cerevisiae were investigated. The suc2 gene deletion strain and the complementary strain were fermented in the media with sucrose as a carbon source on the static condition. It was found that the suc2 gene deletion strain lost the ability to metabolize sucrose while as the complementary strain restored sucrose utilization ability. Sucrose utilization and ethanol production of the complementary strain were higher than that of the wild strain INVSC1. Obviously,suc2 is a key gene that plays a decisive role in the sucrose metabolization of Saccharomyces cerevisiae. So,we think that suc2 might be used as a key point to modify sucrose metabolic pathway.