Trehalase activation in yeasts is mediated by an internal acidification

Area of Science:

• Cellular and Molecular Biology
• Biochemistry
• Yeast Physiology

Background:

• Trehalase activation in yeast has been linked to plasma membrane depolarization.
• Previous studies suggested membrane potential changes mediate trehalase activation.
• The precise mechanism of trehalase activation requires further investigation.

Purpose of the Study:

• To determine the role of membrane potential and pH gradient in yeast trehalase activation.
• To investigate the relationship between electrochemical proton gradient components and trehalase activity.
• To elucidate the signaling pathway for trehalase activation in Saccharomyces cerevisiae.

Main Methods:

• Measured membrane potential using triphenylmethylphosphonium distribution.
• Assessed intracellular pH gradient via benzoic acid distribution.
• Studied the effects of glucose, KCl, carbonyl cyanide m-chlorophenylhydrazone, and nystatin on yeast cells.

Main Results:

• Glucose activated trehalase and caused internal acidification, with minimal effect on membrane potential.
• Cell depolarization with KCl did not alter internal pH or trehalase activity.
• Trehalase activation correlated with intracellular acidification, independent of membrane potential changes.

Conclusions:

• Trehalase activation in Saccharomyces cerevisiae is primarily mediated by intracellular acidification.
• The membrane potential of the plasma membrane is not the direct trigger for trehalase activation.
• Internal acidification, rather than depolarization, is the key factor in activating yeast trehalase.