Regulation of intracellular level of Na+, K+ and glycerol in Saccharomyces cerevisiae under osmotic stress

The intracellular level of Na+ and K+ of S. cerevisiae strain AB1375 revealed that under KCl as well as sorbitol stress, the cationic level was comparable to the level under no stress conditions. On the other hand, there was a sharp drop in the intracellular K+ content and increase in the Na+ content on addition of NaCl to the medium. However, the total cationic level was close to that under control conditions. In addition to changes in the cationic level, an enhanced production and accumulation of glycerol were also observed under osmotic stress. A regulatory mechanism co-ordinating the intracellular concentration of glycerol as well as Na+, K+ content under osmotic stress conditions has been proposed.

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