Genes from Debaryomyces hansenii increase salt tolerance in Saccharomyces cerevisiae W303.

The yeast Debaryomyces hansenii has been chosen as a model for molecular studies of tolerance to NaCl. A gene library was built and transformants of Saccharomyces cerevisiae W303 containing genes from D. hansenii were selected for their ability to grow in the presence of high concentrations of NaCl and/or low concentrations of KCl. In three of these transformants 500 mM NaCl improved growth at pH 7.6 like in D. hansenii but not in S. cerevisiae. One of the plasmids restored growth at 50 microM KCl and K(+) uptake in a mutant of S. cerevisiae lacking genes that encode K(+) transporters.