Preparation and characterization of penicillin acylase immobilized on sepabeads EC-EP carrier

Abstract

This paper reports the covalent immobilization of penicillin G acylase from E. coli on Sepabeads EC-EP, an epoxy-activated polymethacrylic carrier, and describes the properties of the immobilized enzyme. Due to its versatility to mediate hydrolysis of penicillins and semi-synthetic B-lactam antibiotics synthesis reactions, the selected enzyme belongs to a class of biocatalysts of great industrial interest. The immobilized enzyme was characterized in its pH and thermal stability and reaction kinetics. The immobilization of penicillin acylase resulted in a slightly different pH activity profile and temperature optima, indicating that the immobilization by this method imparted the structural and conformational stability to this enzyme. The immobilized enzyme also retained a high catalytic activity and showed the increased thermal stability compared with a free enzyme. By comparison of decimal reduction time values obtained at 50°C, it can be concluded that the immobilized enzyme was approximately 5-fold more stable than a free enzyme. The immobilization procedure developed is quite simple and easily reproduced, and provides a promising solution for the application of penicillin acylase for the purpose of 6-aminopenicillanic acid production.