Transcriptomic analysis of a novel Saccharomyces cerevisiae strain with improved xylose fermentation ability under heat and acid co-stress

Xylose-utilizing yeasts with tolerances to fermentation inhibitors (such as weak organic acids) and high temperature are needed for cost-effective simultaneous saccharification and co-fermentation (SSCF) of lignocellulosic materials. We constructed a novel xylose-assimilating Saccharomyces cerevisiae strain with improved fermentation performance under heat and acid co-stress using the genome shuffling technique. Two xylose-utilizing diploid yeasts with different genetic backgrounds were used as the parental strains for genome shuffling. The hybrid strain Hyb-8 showed significantly higher xylose fermentation ability than both parental strains (Sun049T-Z and Sun224T-K) under co-stress conditions of heat and acids. To screen for genes that might be important for fermentation under heat and acid co-stress, a transcriptomic analysis of hybrid strain Hyb-8 and its parental strains was performed. Total RNA extracted from three Saccharomyces cerevisiae strains (Sun049T-Z, Sun224T-K, and Hyb-8) was used for the transcriptomic analysis by Agilent microarray. Each microarray sample was analyzed in triplicate resulting in total of 9 samples.