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

In this work six psychophilic and psychrotrophic bacterial strains were screened for the presence of different glycosidase activities (alpha-galactosidase, alpha-glucosidase, beta-glucosidase, alpha-mannosidase and beta-glucuronidase). Nine enzymes were found and their elementary characteristics were measured (t(optimum), pH(optimum), K-m, V-lim). Two enzymes with the highest activities at low temperatures were chosen for the next study, i.e. alpha-glucosidase and beta-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 (alpha-glucosidase - 76 kDa, beta-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.