Isolation and Characterization of A β-Primeverosidase-like endo-manner β-Glycosidase from Aspergillus fumigatus AP-20

Abstract

  A novel β-glycosidase-producing microorganism was isolated from soil and identified as Aspergillus fumigatus AP-20 based on its taxonomical characteristics. The enzyme was found to be an extracellular protein in the culture of the isolated fungus and was purified 88-fold by fractionation with ammonium sulfate followed by successive column chromatographies on phenyl-Sepharose HP and Mono P HR. The molecular mass was estimated to be 47 kDa by SDS-PAGE and the isoelectric point to be pH 6.0 by isoelectric focusing. The purified enzyme was highly specific for a substrate, p-nitrophenyl β-primeveroside (6-O-β-D-xylopyranosyl-β-D-glucopyranoside), which was cleaved in an endo-manner into primeverose and p-nitrophenol.