(560av) Polyelectrolytes Enabled Co-Localization of Enzyme Cascades for One-Pot Synthesis
Here we present a method of using polyelectrolyte to co-localize enzyme cascades, in which the polyelectrolyte generates a favorable microenvironment in terms of pH in the vicinity region of the conjugated enzyme and thus enables a high activity and stability.
To demonstrate the effectiveness of this method, we chose chloroperoxidase (CPO) from Caldariomyces fumago and xanthine oxidase (XO) from bovine milk as a model cascade and tested its performance in the oxidization of p-xylene to p-toluic acid. After the conjugation of CPO to polymethacrylic acid (PMAA) whereas XO to chitosan quaternary ammonium salt, respectively, CPO-PMAA@XO-chitosan was obtained by electrostatic interactions between oppositely charged polyelectrolytes. The co-localization of enzymes was confirmed by confocal laser scanning microscopy, which showed the average distance between CPO and XO was 6.2 nm. The oxidization of p-xylene to p-toluic acid operated at various pH showed that, compared to the native counterpart, the CPO-PMAA@XO-chitosan received a 7.6-fold increase in throughput and moreover a wider pH window of activity and stability. The effectiveness of this method was also demonstrated in GOx-PMAA@HRP-chitosan cascade. The enhanced activity and expanded operation window suggests that this assembly method is promising for one-pot enzyme cascade reaction.