title: [Studies on the immobilized penicillin acylase on polymer beads].
abstract: The extracellular penicillin acylase from Bacillus megaterium was immobilized on oxirane group of Eupergit C beads. The apparent activity of the immobilized enzyme was about 1400 u.g-1 (dry weight). The optimal pH and temperature were 8.0 and 55 degrees C for hydrolytic reaction of penicillin G, respectively. The immobilized enzyme was stable in the pH range of 6.0-8.5 and at temperature below 45 degrees C. The apparent Michaelis constant for penicillin G was inhibition constant of phenylacetic acid as competitive 2 x 10(-2) mol.L-1 and Vm was 1.33 mmol.g-1 min-1 (dry weight) at 37 degrees C and PH8.0. The inhibitor and 6-APA as non-competitive inhibitor were 2.8 x 10(-2) mol.L-1 and 0.125 mol.L-1 for the immobilized enzyme at pH 8.0 and 37 degrees C, respectively. The remained activity of the immobilized enzyme was about 80% after operating 200 times for hydrolysis of penicillin G to 6-APA, and the average yield of 6-APA was 89.48%.
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: H
authors.initials: H
authors.lastname: Han
authors.forename: G
authors.initials: G
authors.lastname: Xu
mesh_terms: D001410:Bacillus megaterium / Q000201:enzymology*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D010399:Penicillin Amidase / Q000302:isolation & purification / Q000378:metabolism*; D010400:Penicillin G / Q000378:metabolism; D011108:Polymers / Q000737:chemistry*; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D011108:Polymers; C065843:Eupergit C; D010399:Penicillin Amidase; D010400:Penicillin G