Construction of engineered bacteria for onestep producing alcohol with Jerusalem artichoke

To obtain fusant strains being able to produce ethanol directly from Jerusalem artichoke （Helianthus tuberosus） materials efficiently, the protoplast fusion technique was used and some appropriate conditions were chosen for protoplast preparation and fusion. The protoplast fusion was conducted between Saccharomyces cerevisiae and a penicillium strain obtained by selfscreening with a high yield of inulinase. The abilities of inulinase and ethanol production of detected fusants was determined. Their genetic stability was also studied. Finally, a superior strain named R8 was chosen for inulin alcoholic fermentation. The results showed that the ethanol content of fermented products was 41.16% and the raw sugar utilization rate was 75.52%.