Immobilization of a β-glucosidase and an endoglucanase in ferromagnetic nanoparticles: A study of synergistic effects

Publication date: Available online 31 March 2019Source: Protein Expression and PurificationAuthor(s): Sibeli Carli, Lara Aparecida Buffoni de Campos Carneiro, Richard John Ward, Luana Parras MeleiroAbstractNanoparticles can act as support materials for enzymatic immobilization, introducing a balance of characteristics that modulate the efficiency of biocatalysts, such as specific surface area, resistance to mass transfer and effective enzymatic loading. Magnetic nanoparticles can be easily separated using an external magnetic field, and in this work two recombinant enzymes, the β-glucosidase from Humicola insolens (Bglhi) and the endoglucanase from Scytalidium thermophilum (Egst) were immobilized on synthetized Fe3O4 nanoparticles derivatized with chitosan/glutaraldehyde/N-(5-amino-1-carboxy-pentyl) iminodiacetic acid and functionalized with NiCl2. The immobilization yields were about 20% for Bglhi and Egst with efficiencies of 132% and 115%, respectively. The two enzymes were also co-immobilized with yield was about 49%. The optimal temperatures of the immobilized enzymes were 70 °C and 55 °C for Egst and Bglhi, respectively. Egst hydrolyzed CMC in the presence of 4 mM MnCl2 with Vmax = 625.0 ± 6.7 U mg−1 and KM = 6.4 ± 0.5 mg mL−1 resulting in a catalytic efficiency (kcat/KM) of 107.4 ± 5.4 mg−1 s−1 mL. Bglhi hydrolyzed pNP-Glc with Vmax = 52.7 ± 2.7 U mg−1 and KM = 0.23 ± 0.01 mM resulting in a cat...
Source: Protein Expression and Purification - Category: Biochemistry Source Type: research