Thermal inactivation of immobilized penicillin acylase in the presence of substrate and products

Illanes A.; Altamirano, C; Zuñiga, M. E.

Keywords: kinetics, substrate, catalysis, stability, acid, decay, enzyme, modulation, molecules, inactivation, acids, bacterial, acylase, substrates, coli, penicillin, article, immobilization, organic, bioreactors, thermal, compounds, amidase, nonhuman, thermostability, G, Escherichia, Aromatic, 6, Aminopenicillanic, phenylacetic

Abstract

Inactivation of immobilized penicillin acylase has been studied in the presence of substrate (penicillin G) and products (phenylacetic acid and 6- aminopenicillanic acid), under the hypothesis that substances which interact with the enzyme molecule during catalysis will have an effect on enzyme stability. The kinetics of immobilized penicillin acylase inactivation was a multistage process, decay constants being evaluated for the free-enzyme and enzyme complexes, from whose values modulation factors were determined for the effectors in each enzyme complex at each stage. 6-Aminopenicillanic acid and penicillin G stabilized the enzyme in the first stage of decay. Modulation factors in that stage were 0.96 for penicillin G and 0.98 for 6- aminopenicillanic acid. Phenylacetic acid increased the rate of inactivation in both stages, modulating factors being -2.31 and -2.23, respectively. Modulation factors influence enzyme performance in a reactor and are useful parameters for a proper evaluation. Inactivation of immobilized penicillin acylase has been studied in the presence of substrate (penicillin G) and products (phenylacetic acid and 6-aminopenicillanic acid), under the hypothesis that substances which interact with the enzyme molecule during catalysis will have an effect on enzyme stability. The kinetics of immobilized penicillin acylase inactivation was a multistage process, decay constants being evaluated for the free-enzyme and enzyme complexes, from whose values modulation factors were determined for the effectors in each enzyme complex at each stage. 6-Aminopenicillanic acid and penicillin G stabilized the enzyme in the first stage of decay. Modulation factors in that stage were 0.96 for penicillin G and 0.98 for 6-aminopenicillanic acid. Phenylacetic acid increased the rate of inactivation in both stages, modulating factors being -2.31 and -2.23, respectively. Modulation factors influence enzyme performance in a reactor and are useful parameters for a proper evaluation.

Más información

Título de la Revista: BIOTECHNOLOGY AND BIOENGINEERING
Volumen: 50
Número: 6
Editorial: Wiley
Fecha de publicación: 1996
Página de inicio: 609
Página final: 616
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-15844369202&partnerID=q2rCbXpz