Hydrolysis of phosphomonoesters in nucleotides by cerium(IV) ions. Highly selective hydrolysis of monoester over diester in concentrated buffers

Abstract

Phosphomonoesters in nucleotides are efficiently hydrolysed by Ce^IV ions under physiological conditions. The half-lives of the residues at pH 7.2 and 50 °C ([Ce^IV] = 10 mM) are around 10 min. Phosphomonoester hydrolysis by Ce^IV ions is faster than the hydrolysis of phosphodiesters. Significantly, the selectivity for monoester hydrolysis over diester hydrolysis is remarkably increased by using concentrated buffer solutions (TRIS and HEPES). In 500 mM TRIS buffer, pdA and dAp are hydrolysed 500- and 580-fold faster than is d(ApA), whereas the corresponding ratios in 50 mM TRIS buffer are 85 and 90 respectively. Selective removal of the terminal monophosphate from d(pApA) is achieved by Ce^IV in these concentrated buffers.

References

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