Proteomic changes in response to potassium starvation in the extremophilic yeast Debaryomyces hansenii.

In this work, we performed for the first time a proteomic approach to the processes induced by long-term potassium starvation in the halotolerant yeast Debaryomyces hansenii. The proteomic profile under this ionic stress conditions shows that important changes in gene expression take place as an adaptive response. We found a significant protein expression repression as well as metabolic changes such as the inhibition of the upper part of the glycolysis, the amino acid synthesis, and the Krebs cycle. On the other hand, genes related to stress responses, protein degradation, and sterols synthesis were upregulated in response to potassium deprivation. The findings in this study provide important information about how this particular yeast copes with ionic stress at molecular levels, which might further enrich the global understanding of salt tolerance processes in eukaryal systems and moreover highlighting the importance of the 'omics' approaches as a complement to the classical physiological studies.