α-glucosidase and β-glucosidase from psychrotrophic strain Arthrobacter sp. C2-2

Abstract

In this work six psychophilic and psychrotrophic bacterial strains were screened for the presence of different glycosidase activities (α-galactosidase, α-glucosidase, β-glucosidase, α-mannosidase and β-glucuronidase). Nine enzymes were found and their elementary characteristics were measured (toptimum, pH optimum, Km, Vlim). Two enzymes with the highest activities at low temperatures were chosen for the next study, i.e. α-glucosidase and β-glucosidase from the psychrotrophic strain Arthrobacter sp. C2-2. These enzymes were purified by ammonium sulphate precipitation, by chromatography with hydrophobic interaction, and by ion-exchange chromatography. Their molecular weights (α-glucosidase - 76 kDa, β-glucosidase - 93 kDa) were determined by gel chromatography. In addition to this, it was verified that both of these enzymes are able to catalyse the transglycosylation reaction with the saccharidic donor and acceptor.