Purification, characterization and gene analysis of a new α-glucosidase from shiraia sp. SUPER-H168

摘要: A new α-glucosidase from Shiraia sp. SUPER-H168 under solid-state fermentation was purified by alcohol precipitation and anion-exchange gel filtration chromatography. The optimum pH temperature of the were 4.5 60 °C, respectively, using p-nitrophenyl-α-glucopyranoside (α-pNPG) as a substrate. Ten millimoles sodium dodecyl sulfate, Fe2+, Cu2+, Ag+ reduced enzyme activity to 0.7, 7.6, 26.0, 6.2 %, that untreated enzyme. K m, V max, k cat/K m 0.52 mM, 3.76 U mg−1, 1.3 × 104 L s−1 mol−1, respectively. with maltose 0.62 mM. Transglycosylation activities observed sucrose substrates, while there no transglycosylation trehalose. DNA its corresponding full-length cDNA cloned analyzed. coding region consisted 2997-bp open reading frame encoding 998-amino acid protein 22-amino signal peptide; one 48-bp intron located. monomeric predicted molecular mass 108.2 kDa isoelectric point 5.08. neighbor-joining phylogenetic tree demonstrated is an ascomycetes α-glucosidase. This first report filamentous fungus had good glycoside hydrolysis α-pNPG, conversion into