Abstract: In order to obtain the strains producing fuel ethanol,the engineering strain Saccharomyces cerevisiae,which may ferment using sugarcane juice to yield high ethanol,were constructed by genetic engineering. In other words,the inositol-3-phosphate synthase gene（ino1）was over-expressed in S. cerevisiae;the antibiotic resistance gene（kanMX）were knocked out,thus recombinant S. cerevisiae was acquired. Further,the tolerances（survivability）of the over-expressed strains to ethanol were analyzed. The sugarcane juice was used as a carbon source in the fermentation,and the ethanol content in the fermentation broth of strains was detected by gas chromatography. The experimental results showed that over-expressed strains YI2-1tolerated 19%（V/V）ethanol. The 20^oBx of sugarcane juice was employed in the anaerobic fermentation,which yielded 13.10%（V/V）of the ethanol,and this was 8.55% more than that by the initial strain. The biggest output of ethanol by the over-expressed strain YI2-1△KP was accumulated to 13.17%（V/V）,and this was 9.16% more than that by the original one. This study indicates that over-expression of ino1 gene efficiently enhances the cell viability and tolerance of S. cerevisiae to ethanol and the constructed strain S. cerevisiae is proved to highly yield ethanol by the fermentation of sugarcane juice.

Key words: Saccharomyces cerevisiae, over-expression of ino1 gene, fuel ethanol, tolerance to ethanol