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A study was conducted on the influence of Na+ and anions on growth and dimorphic potential of the pathogenic yeast Candida albicans. The findings indicate Na+ inhibition of germ tube outgrowth at high ambient pH and that dimorphic transition is promoted by gluconate. Although the exact site of Na+ action remains unknown, the anion effects may be interpreted in terms of anion-exchanger and channel activity during the modulation of cytosolic pH.

A comparison of the relative tolerance to osmotic stress and to alkali cation toxicity of the fermentive yeast Saccharomyces cerevisiae and the respiratory yeast Candida tropicalis was made. Glucose media distinguished that C. tropicalis has a poor adaptation to osmotic stress and exhibited reduced glycerol production compared to S. cerevisiae. Trehalose was also determined as an important osmoresponsive solute in S. cerevisiae in the absence of glucose repression.

Deletion of the NHA1 gene of Saccharomyces cerevisiae wild type strains, lead to higher sensitivity to both K+ and Na+ at acidic pH. High K+ and Na+ efflux seen on alkalinization of the cytoplasm suggests a role for Nha1p in the regulation of intracellular pH. The Nha1 alkalication antiporter is found to be responsible for growth on high concentrations of KC1 and NaC1.