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Published on: November 3, 2018
Aggregation of Phosphates Enhances Enzyme Activity in Aqueous Solution
Sourav Bajpayee1, Velsuba Murugan2, William S Price3
1School of Chemistry, UNSW Sydney, Sydney, NSW, Australia.
Abstract:
Diffusion coefficients and viscosities of tetrabutylammonium dihydrogen phosphate ([NBu4]+[H2PO4]-), potassium dihydrogen phosphate (K+[H2PO4]-), tetrabutylammonium bromide ([NBu4]+[Br]-), tetrabutylammonium chloride ([NBu4]+[Cl]-), and biologically relevant phosphate salts adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP) were measured in aqueous solutions as a function of concentration across millimolar concentrations. The [NBu4]+ cation makes the solutions viscous at high millimolar concentrations, and there was no significant evidence of aggregation of the [H2PO4]- anion. At higher millimolar concentrations, ATP, ADP, and AMP aggregate in aqueous solutions. The increasing concentration of ATP and ADP leads to increased activity of three different enzymes: cytochrome c, laccase, and horseradish peroxidase.
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