Publications by authors named "Daiki Harita"
Article Synopsis
- Myxococcus xanthus uses polyphosphate kinase 1 (Ppk1) to synthesize polyphosphates (polyPs) and degrades them with exopolyphosphatases Ppx1 and Ppx2, playing a crucial role in managing energy levels during development.
- The study shows that Ppk1 mutants die earlier in stationary phase, but don't differ significantly in growth or structure compared to wild types in phosphate-starved or other nutrient-deficient conditions.
- Elevated intracellular polyP levels and altered adenylate energy charge (AEC) ratios in mutants indicate that polyPs are vital for energy balance, particularly in spore germination.
Polyphosphate kinase 1 (Ppk1) generates polyphosphates (polyPs) by catalyzing phosphate transfer from ATP. In the presence of ATP, Myxococcus xanthus Ppk1 showed the highest activity with polyP60-70 but also showed high activity with orthophosphate and pyrophosphate. Ppk1 synthesizes long-chain polyPs with >1 000 phosphate residues from orthophosphate or pyrophosphate present in high concentrations, suggesting that in M.
View Article and Find Full Text PDFEnzymatic properties of Myxococcus xanthus exopolyphosphatases mxPpx1 and mxPpx2.
Biochim Biophys Acta Proteins Proteom
August 2021
Myxococcus xanthus possesses two exopolyphosphatases, mxPpx1 and mxPpx2, which belong to the family of Ppx/GppA phosphatases; however, their catalytic properties have not been described. mxPpx1 and mxPpx2 contain 311 and 505 amino acid residues, respectively; mxPpx2 has an additional C-terminal region, which corresponds to the metal-dependent HDc phosphohydrolase domain. mxPpx1 mainly hydrolyzed short-chain polyPs (polyP and polyP), whereas mxPpx2 preferred long-chain polyP and polyP.
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