The influence of isoenzymes composition and chemical modification on horseradish peroxidase@ZIF-8 bio-composite performance

Abstract

Many articles in the literature deal with horseradish peroxidase (HRP) biomineralization,but none pay attention to the isoenzyme composition of commercial HRP or the influence of thecarbohydrate component of the protein molecule on the biomineralization process. To study theimpact of these factors, we performed periodate oxidation of commercial HRP and a purified HRP-Cisoform for biomineralization within ZIF-8. With purified HRP, enzyme@ZIF-8 biocomposites withhigher activity were obtained, while periodate oxidation of the carbohydrate component of bothcommercial HRP and purified HRP-C yields biocomposites with very high activity in acetate bufferthat does not degrade the ZIF-8 structure. Using acetate instead of phosphate buffer can prevent thefalse high activity of HRP@ZIF-8 biocomposites caused by the degradation of ZIF-8 coating. At thesame time, purification and especially oxidation of the carbohydrate component of enzymes prior tobiomineralization lead to significantly improved activity of the biocomposites.