论文部分内容阅读
Yeast cells that withstand high temperature is a continuous significant prominence in consolidated bioprocessing of ethanol production in where high temperature is a desirable trait to reduce cooling cost and provides an optimal environment for biomass hydrolyzing enzymes.However, most of the wild type Saccharomyces cerevisiaestrains requires around 28℃ to 37℃ for optimum growth.With the aim of obtaining high thermotolerant yeast, we have transformed zinc-finger-based artificial transcripton factors (ATFs) containing UME6 effector domain which recognize targeting sites in chromosomes with distinct specificities to reprogram global gene expression circuits in yeast ceils.Competent yeast cells were electrotransformed with 10 ng of ATF library, with a transformation efficiency of 1 × 105cfu/μg DNA.The resulting transformantswere analyzed for thermotolerance at 42℃.Surprisingly, successful transformants could grow faster in liquid YPD medium than in YPD agar medium.Thereafter, ethanol fermentation was performed by mutant S.cerevisiae JM01 and wild type S.cerevisiae ZQ5 at 42℃.Ethanol production by the thermal mutant strain S.cerevisiae JM01 was two-fold higher than that of wild type S.cerevisiae ZQ5 at 60 hr fermentation.These results clearly indicate that the thermotolerant S.cerevisiae JM01 is an attractive ethanol producer for high-temperature ethanol fermentation.