Enhanced laccase activity of biocatalytic hybrid copper hydroxide nanocages

Publication date: Available online 17 May 2019Source: Enzyme and Microbial TechnologyAuthor(s): Omar Silva-Torres, Luis Bojorquez-Vazquez, Andrey Simakov, Rafael Vazquez-DuhaltAbstractNanobiocatalysis is the combination of the unique properties of nano-sized materials and the efficiency and sophistication of catalytic properties of enzymes. In this work, Cu(OH)2 nanocages with an mean size of 170 nm were synthesized and used as a support for the covalent conjugation with fungal ligninolytic enzymes; versatile peroxidase and laccase. Both enzymes have the ability to degrade a wide range of pollutants. The nanocages were characterized, the orthorhombic arrangement of the nanocages was confirmed and TEM images showed that the nanocages are composed of nano-ribbons stacked around the particles. Interestingly, bioconjugated laccase-nanocages exhibited up to 18-times higher catalytic rate that these found for free enzyme, while activity of versatile peroxidase-nanocages was considerably reduced. The total turnover number for free laccase and laccase-nanocages are similar, suggesting that the activity increase is not due to the supply of Cu ions to a possible Cu-depleted active site of laccase. This enhancement of laccase activity when immobilized enzyme onto Cu(OH)2 nanocages could be important for the actual and potential industrial uses of laccases.Graphical abstract
Source: Enzyme and Microbial Technology - Category: Biotechnology Source Type: research