Regulation of Saccharomyces cerevisiae maltose fermentation by cold temperature and CSF1

We studied the influence of cold temperature (10ºC) on the fermentation of maltose by a S. cerevisiae wild-type strain, and a csf1D mutant impaired in glucose and leucine uptake at low temperatures. Cold temperature affected the fermentation kinetics by decreasing the growth rate and the final cell yield, with almost no ethanol been produced from maltose by the wild-type cells at 10ºC. The csf1D strain did not grew on maltose when cultured at 10ºC, indicating that the CSF1 gene is also required for maltose consumption at low temperatures. However, this mutant also showed increased inhibition of glucose and maltose fermentation under salt stress, indicating that CSF1 is probably involved in the regulation of other physiological processes, including ion homeostasis.