Comparative biochemistry of four polyester (PET) hydrolases

Abstract

The potential of bioprocessing in a circular plastic economy has strongly stimulated research in enzymatic egradation of different synthetic resins. Particular interest has been devoted to the commonly used polyester, oly(ethylene terephthalate) (PET), and a number of PET hydrolases have been described. However, a kinetic ramework for comparisons of PET hydrolases (or other plastic degrading enzymes) acting on the insoluble ubstrate, has not been established. Here, we propose such a framework and test it against kinetic easurements on four PET hydrolases. The analysis provided values of kcat and KM, as well as an apparent specificity constant in the conventional units of M-1s-1. These parameters, together with experimental values for the umber of enzyme attack sites on the PET surface, enabled comparative analyses...