Investigation into struvite precipitation: A commonly encountered problem during fermentations on chemically defined media.

Chemically defined mineral media are widely used in bioprocesses, as these show less batch to batch variation compared with complex media. Nonetheless, the recommended media formulations often lead to the formation of precipitants at elevated pH values. These precipitates are insoluble and reduce the availability of macronutrients to the cells, which can result in limiting growth rates and lower productivity.

Biotechnological production of polyphosphate from industrial wash water.

Phosphate is mined from phosphate rock, which is a limited resource on a human time scale. For a sustainable phosphate supply, strategies for efficient use and recycling of phosphate must be developed. A German chemical company produces annually wash water containing phosphate and other inorganic substances (e.

Biotechnological synthesis of water-soluble food-grade polyphosphate with Saccharomyces cerevisiae.

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.

Methods for the Analysis of Polyphosphate in the Life Sciences.

Inorganic polyphosphate (polyP) is the polymer of orthophosphate and can be found in all living organisms. For polyP characterization, one or more of six parameters are of interest: the molecular structure (linear, cyclic, or branched), the concentration, the average chain length, the chain length distribution, the cellular localization, and the cation composition. Here, the merits, limitations, and critical parameters of the state-of-the-art methods for the analysis of the six parameters from the life sciences are discussed.

Polyphosphate Chain Length Determination in the Range of Two to Several Hundred P-Subunits with a New Enzyme Assay and P NMR.

Currently, P NMR is the only analytical method that quantitatively determines the average chain length of long inorganic polyphosphate (>80 P-subunits). In this study, an enzyme assay is presented that determines the average chain length of polyphosphate in the range of two to several hundred P-subunits. In the enzyme assay, the average polyP chain length is calculated by dividing the total polyphosphate concentration by the concentration of the polyphosphate chains.

Saccharomyces cerevisiae containing 28% polyphosphate and production of a polyphosphate-rich yeast extract thereof.

Currently, inorganic polyphosphate is chemically synthesized from phosphate rock and added directly to food products. Yeast extract is a concentrate of soluble fractions of Saccharomyces cerevisiae and is, as a food additive, generally regarded as safe. The aim of this study was to biotechnologically produce a naturally polyphosphate-rich yeast extract.

Analytical polyphosphate extraction from Saccharomyces cerevisiae.

In Saccharomyces cerevisiae, inorganic polyphosphate is analyzed by polyphosphate extraction and subsequent quantification. Recently, we developed a method for polyphosphate quantification, and length determination of short chain polyphosphate. However, the lack of a simple, optimized and validated method for analytical polyphosphate extraction has both hindered the advance in this research field, and prevented comparability of results between laboratories.

Enzymatic quantification and length determination of polyphosphate down to a chain length of two.

Polyacrylamide gel electrophoresis, being the current method of choice for length determination of inorganic polyphosphate (polyP), requires a sequencing apparatus, relies on commercially not available polyP length standards and yields only a chain length distribution. State of the art polyP quantification involves enzymatic hydrolysis of polyP to orthophosphate with the Saccharomyces cerevisiae exopolyphosphatase 1 (scPpx1p) and subsequent colorimetric orthophosphate detection. Because scPpx1p leaves one pyrophosphate per polyP, short chain polyPs are only partially detected.