Biotechnological synthesis of water‐soluble food‐grade polyphosphate with Saccharomyces cerevisiae. Issue 7 (4th April 2020)

• Record Type: Journal Article
• Authors: Christ, Jonas Johannes; Smith, Stephanie A.; Willbold, Sabine; Morrissey, James H.; Blank, Lars Mathias
• Is Part Of: Biotechnology and bioengineering. Volume 117:Issue 7(2020)
• Page Start: 2089
• Page End: 2099
• Publication Date: 2020-04-04
• Subjects: biosynthesis -- food additive -- natural products -- polymers -- polyphosphate; Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.27337
• Languages: English
• ISSNs: 0006-3592

Abstract

Abstract: Inorganic polyphosphate (polyP) is the polymer of phosphate. Water‐soluble polyPs with average chain lengths of 2–40 P‐subunits are widely used as food additives and are currently synthesized chemically. An environmentally friendly highly scalable process to biosynthesize water‐soluble food‐grade polyP in powder form (termed bio‐polyP) is presented in this study. After incubation in a phosphate‐free medium, generally regarded as safe wild‐type baker's yeast ( Saccharomyces cerevisiae ) took up phosphate and intracellularly polymerized it into 26.5% polyP (as KPO3, in cell dry weight). The cells were lyzed by freeze‐thawing and gentle heat treatment (10 min, 70°C). Protein and nucleic acid were removed from the soluble cell components by precipitation with 50 mM HCl. Two chain length fractions (42 and 11P‐subunits average polyP chain length, purity on a par with chemically produced polyP) were obtained by fractional polyP precipitation (Fraction 1 was precipitated with 100 mM NaCl and 0.15 vol ethanol, and Fraction 2 with 1 final vol ethanol), drying, and milling. The physicochemical properties of bio‐polyP were analyzed with an enzyme assay, 31 P nuclear magnetic resonance spectroscopy, and polyacrylamide gel electrophoresis, among others. An envisaged application of the process is phosphate recycling from waste streams into high‐value bio‐polyP. Abstract : The biosynthesis of pure water‐soluble food‐grade polyphosphate is presented. After being starved for phosphate, wild‐type baker's yeast ( Saccharomyces cerevisiae, background picture) accumulated phosphate and polymerized it intracellularly into polyphosphate. The polyphosphate was purified from S. cerevisiae in an economic highly scalable process.