Characterization of acyl adenyl anhydrides: Differences in the hydrolytic rates of fatty acyl-AMP and aminoacyl-AMP derivatives

An improved procedure has been developed to prepare RCOOPO₂-Ado (R = C₆H₁₃ and C₁₅H₃₁), the intermediate in the enzymatic synthesis of acyl-CoA's. The product has been characterized by spectral methods which, in turn, were used to define the hydrolysis rates of RCO-AMP. When R is a fatty acyl group, the hydrolysis rate is 10-fold slower than when R is aminoacyl. In both cases, the hydrolysis rate is enhanced by Mg²⁺. We speculate that the rate acceleration is due to intramolecular participation of the second carbonyl group in the aminoacyl residue.