The application of biotransformations in solid phase synthesis is an attractive alternative to chemical methodologies. An important issue that needs to be addressed in this context is accessibility of functional groups within a porous polymer to the biocatalyst. This paper shows that such accessibility can be improved for penicillin G amidase by introducing permanent charges into the polymer. The effect appears to be due to better swelling of the polymer in buffer and to electrostatic interactions between polymer and enzyme.
