The thermophilic yeast Hansenula polymorpha does not require trehalose synthesis for growth at high temperatures but does for normal acquisition of thermotolerance

The TPS1 gene from Hansenula polymorpha, which encodes trehalose-6-phosphat e (Tre6P) synthase, has been isolated and characterized. The deletion of TP S1 rendered H. polymorpha cells incapable of trehalose synthesis under cond itions where wild-type cells normally accumulate high levels of trehalose. Interestingly, the loss of Tre6P synthase did not cause any obvious growth defects on a glucose-containing medium, even at high temperatures, but seri ously compromised the cells' ability to acquire thermotolerance.