Polyphosphate Accumulation Is Determined by Zinc and Inositol in Saccharomyces cerevisiae

Area of Science:

• Biotechnology and Industrial Microbiology
• Biochemistry and Molecular Biology

Background:

• Polyphosphate (polyP) is a versatile polymer with significant biological and industrial relevance.
• Chemical synthesis of polyP is energy-intensive and limits chain length, necessitating sustainable biological production methods.
• Saccharomyces cerevisiae shows potential for high polyP accumulation, contingent on phosphate (P_i) starvation and refeeding cycles.

Purpose of the Study:

• To elucidate the specific roles of trace elements and vitamins in enhancing polyP accumulation in Saccharomyces cerevisiae.
• To identify key components that drive polyP hyperaccumulation in diverse yeast strains.
• To investigate the impact of these components on yeast energy metabolism and relevant signaling pathways.

Main Methods:

• Cultivation of various laboratory and industrial Saccharomyces cerevisiae strains under controlled conditions.
• Supplementation of cultivation media with specific trace elements and vitamins during phosphate starvation.
• Analysis of polyP content, energy metabolism, and the phosphate-responsive (PHO) signaling pathway.

Main Results:

• Inositol and zinc were identified as critical drivers of polyP accumulation across different S. cerevisiae strains.
• Zinc supplementation was shown to enhance the phosphate-responsive (PHO) pathway activity during P_i starvation.
• The precise mechanism by which inositol influences polyP hyperaccumulation, independent of the PHO pathway, requires further investigation.

Conclusions:

• Inositol and zinc are key factors for optimizing biological polyphosphate production in Saccharomyces cerevisiae.
• Zinc's role in activating the PHO pathway provides a target for enhancing polyP synthesis.
• Further research into inositol's function can unlock new strategies for maximizing polyP yields in yeast.