MODIFICATION OF ENZYME PROPERTIES BY THE USE OF INHIBITORS DURING THEIR STABILIZATION BY MULTIPOINT COVALENT ATTACHMENT

The effect of a number of inhibitors adsorbed at the active site of penicillin acylase during immobilisation/stabilisation is reported. Each inhibitor, when it is adsorbed at the active centre of penicillin acylase promotes a specific enzymatic conformation which remains fixed after the stabilisation process by multipoint covalent attachment to pre-existing supports. A number of inhibitors: penicillin sulfoxide, phenylacetic acid, mandelic acid, and phenylglycine were employed to induce conformational changes. The activity towards different substrates of the enzyme derivative (in hydrolysis and in synthesis) was determined. The stability of the derivatives was also measured. This technique provides a broad spectrum of enzymatic derivatives with a range of activity/stability depending on the inhibitors used in their stabilisation. The resulting choice offers a considerably increased potential for the use of the enzyme since one can select a derivative which will specifically catalyse the reaction of interest.