Genomic and transcriptomic analyses of the Chinese Maotai -flavored liquor yeast MT1 revealed its unique multi-carbon co-utilization

Background Revealing genetic mechanisms behind specific physiological characteristics of Saccharomyces cerevisiae from specific environments is important for industrial applications and requires precise understanding. Results Maotai strain MT1 was isolated from the complicated Chinese Maotai -flavored liquor-making environment with extremely high temperatures, and acidic and ethanol stresses. Compared with the type strain S288c, MT1 can tolerate high acidity (pH 2.0), high ethanol levels (16 %) and high temperatures (44 °C). In addition, MT1 can simultaneously utilize various sugars, including glucose, sucrose, galactose, maltose, melibiose, trehalose, raffinose and turanose. Genomic comparisons identified a distinct MT1 genome, 0.5 Mb smaller than that of S288c. There are 145 MT1-specific genes that are not in S288c, including MEL 1, MAL 63, KHR1 , BIO1 and BIO6 . A transcriptional comparison indicated that HXT5 and HXT13 , which are theoretically repressed by glucose, were no longer inhibited in MT1 and were highly expressed even in a medium containing 70 g/L glucose. Thus, other sugars may be co-utilized with glucose by MT1 without diauxic growth. Conclusions Based on a functional genomics analysis, we revealed the genetic basis and evolutionary mechanisms underlying the traits of the Chinese Maotai -flavored yeast MT1. This work provides new insights for the genetic breeding of yeast and also enriches the genetic resources of yeast.