Selective Phosphonylation of 5′-Adenosine Monophosphate (5′-AMP) via Pyrophosphite [PPi(III)]

We describe here experiments which demonstrate the selective phospho-transfer from a plausibly prebiotic condensed phosphorus (P) salt, pyrophosphite [H(2)P(2)O(5) (2−); PPi(III)], to the phosphate group of 5′-adenosine mono phosphate (5′-AMP). We show further that this P-transfer process is accelerated both by divalent metal ions (M(2+)) and by organic co-factors such as acetate (AcO(−)). In this specific case of P-transfer from PPi(III) to 5′-AMP, we show a synergistic enhancement of transfer in the combined presence of M(2+) & AcO(−). Isotopic labelling studies demonstrate that hydrolysis of the phosphonylated 5′-AMP, [P(III)P(V)-5′-AMP], proceeds via nuceophilic attack of water at the Pi(III) terminus.