Identification of salt-tolerant gene HOG1 in Torulopsis versatilis

To understand the osmo-adaptation mechanism in Torulopsis versatilis (T), we investigated the salt-tolerant gene HOG1 from the wild-type and a salt-tolerant mutant strain (T5) constructed using genome shuffling. The HOG1 genes from T and T5 were sequenced and revealed several mutations had occurred. The expression level of T5HOG1 was stronger than that of THOG1, indicating a reason for the increase of salt-tolerance in T. versatilis. Moreover, overexpression of T5HOG1 and THOG1 improved the tolerance of salt in Saccharomyces cerevisiae. Identification and overexpression of THOG1 and T5HOG1 from the wild-type T. versatilis and the mutant T. versatilis, respectively, play an important role for the osmo-adaption mechanism of the T. versatilis used in soy-sauce fermentation.