Modelling the enzymatic deacylation of penicillin G: Equilibrium and kinetic considerations

L. A.M. Van Der Wielen, M. J. Van Buel, A. J.J. Straathof, K. Ch A.M. Luyben

Research output: Contribution to journalArticlepeer-review

Abstract

The equilibrium position and kinetics of the enzymatic hydrolysis of penicillin G are complex functions of the thermodynamic state of the reaction system. It is desirable to describe the equilibrium position and the course of the deacylation reaction using a consistent basis, preferably with one single set of parameters. Taking the weak electrolytic nature of the reactants into account, an equilibrium model has been derived which incorporates the effects of thermodynamic non-ideality in terms of electrostatic interactions only. The effects of ionic strength can be described within the experimental error. Multiple ionic forms of the reactants coexist, of which one is assumed to be the actual reacting species. A mechanistic kinetic model has been developed which takes the fraction of this species into account. When the anionic forms of the reactants were assumed to be the actual reacting species, the best description of the experimental curves was obtained. However, when compared to a model which takes overall concentrations into account, the improvement is very modest because in the relevant pH-interval, the reactants remain primarily anionic. Using the fully anionic framework, the model has a broad range of validity in terms of reactant concentrations and pH-values and may be applied for the optimization of industrial deacylation reactors.

Original languageEnglish
Pages (from-to)121-146
Number of pages26
JournalBiocatalysis and Biotransformation
Volume15
Issue number2
DOIs
Publication statusPublished - 1997
Externally publishedYes

Keywords

  • 6-aminopenicillanic acid
  • Electrolytes
  • Kinetics
  • Penicillin G acylase
  • Phenylacetic acid
  • Thermodynamics

Fingerprint

Dive into the research topics of 'Modelling the enzymatic deacylation of penicillin G: Equilibrium and kinetic considerations'. Together they form a unique fingerprint.

Cite this