Control of enzyme hydration in penicillin amidase catalysed synthesis of amide bond

Penicillin amidase catalyses the synthesis of amide bond in very high yield (>98%), using equimolar concentrations of the amine and the phenylacetic components. In situ hydrated phosphates were employed for controlling the water activity in a benzene/water system (97:3 v/v), where the water is taken up by the salt with formation of the hydrated species.