Abstract:
Hydrolysis of phosphate containing compounds is important chemical reaction involved in
many life processes such as DNA scission, cell division and organelle movement. Density
functional theory calculations at M06-2X/6-31+G* and B3LYP/6-31+G** level of theory
were carried out to calculate the mechanism of hydrolysis of phosphate monoester. For
these calculations, two different starting set-ups of phosphate monoester, each differing
with respect to the number of water molecules, were chosen. The stationary points along
the potential energy surface that connect the reactant and the product structure were
identified. The findings show that the energy barrier of the uncatalyzed hydrolysis of
phosphate monoester in gas-phase is in the range of 37 to 48 kcal mol-1
. The mechanism
of hydrolysis involves only a single water molecule. The stationary points along the
minimum energy pathway of phosphate monoester hydrolysis involve the characteristics
of both sequential (dissociative) as well as concurrent (associative) mechanisms. Adding
explicit water molecule or the incorporation of implicit solvation model lower the energy
barrier of hydrolysis.
