Regulation and Characterization of Acid and Alkaline Phosphatase in Yeast

SUMMARY: The activity of acid and alkaline phosphatase in baker's yeast is de-repressed when the organisms are starved of phosphate. Mutants lacking phosphatase activity and mutants with constitutive phosphatase synthesis were isolated. In all of them acid and alkaline phosphatases were affected simultaneously. Nevertheless, characterization of these two enzymes by sensitivity to inhibition by orthophosphate, temperature inactivation, proteolytic digestion and cation dependence showed that they were clearly distinct. It is suggested that these two enzymes share a common genetic and structural component.