Data for Extracellular Phosphate Modulation and Polyphosphate Accumulation by Corynebacterium matruchotii and Streptococcus mutans

Abstract

An alternative and understudied microbial mechanism that may influence demineralization is the microbially mediated ion exchange of Ca2+ and orthophosphate (Pi), which alters the saturation state of the mineral species within the surface enamel. There is a need to examine the ability of members of the oral microbiome to modulate Ca2+ and Pi, which control mineral solubility, in order to effectively evaluate mineralization therapies to improve oral health. (2) Methods: Pi uptake was measured using an ascorbic acid assay during a BHI liquid culture growth of Corynebacterium matruchotii and Streptococcus mutans for up to 20 h. The initial and endpoint medium Ca2+ levels were measured using ICP-OES. Bacterial cells were examined at different growth stages using DAPI/polyP binding emission at 525 nm to detect the presence of internalized macromolecules of polyphosphates (polyP) that could drive Pi uptake. (3) Results: C. matruchotii (p = 0.0061) substantially accumulated Pi (3.84 mmol/L), with a concomitant formation of polyP. In contrast, S. mutans did not take up Pi or accumulate polyP. No significant Ca2+ drawdown in the media was observed in either strain. (4) Conclusions: This study suggests that when examining the future efficacy of prevention technologies to improve, in vitro assays may consider including specific oral bacteria capable of substantial Pi uptake.