초록
Several recombinant Kluyveromyces marxianus strains were constructed through overexpressing the Neurospora crassa xylose reductase genes. YZJ015, which maintained the original xylitol dehydrogenase gene, produced xylitol with the highest productivity (1.49gL<SUP>-1</SUP>h<SUP>-1</SUP>) from 100gL<SUP>-1</SUP> xylose at 42<SUP>o</SUP>C. Even at 45<SUP>o</SUP>C, YZJ015 was still able to produce 60.03gL<SUP>-1</SUP> xylitol from 100gL<SUP>-1</SUP> xylose with a productivity of 1.25gL<SUP>-1</SUP>h<SUP>-1</SUP>. In addition, for 20 rounds of cell recycling at 42<SUP>o</SUP>C, YZJ015 produced 71.35gL<SUP>-1</SUP> xylitol from 100gL<SUP>-1</SUP> xylose with a productivity of 4.43gL<SUP>-1</SUP>h<SUP>-1</SUP> per cycle. YZJ017, in which the xylitol dehydrogenase gene was disrupted, produced 100.02gL<SUP>-1</SUP> xylitol at a yield of 1.01gg<SUP>-1</SUP> from 100gL<SUP>-1</SUP> xylose with 40gL<SUP>-1</SUP> glycerol as co-substrate at 42<SUP>o</SUP>C. These engineered strains provide an excellent foundation for xylitol production at elevated temperatures.