title: β-glucosidase from Penicillium aculeatum hydrolyzes exo-, 3-O-, and 6-O-β-glucosides but not 20-O-β-glucoside and other glycosides of ginsenosides.
abstract: A novel β-glucosidase from Penicillium aculeatum was purified as a single 110.5-kDa band on SDS-PAGE with a specific activity of 75.4 U mg⁻¹ by salt precipitation and Hi-Trap Q HP and Resource Q ion exchange chromatographies. The purified enzyme was identified as a member of the glycoside hydrolase 3 family based on its amino acid sequence. The hydrolysis activity for p-nitrophenyl-β-D-glucopyranoside was optimal at pH 4.5 and 70 °C with a half-life of 55 h. The enzyme hydrolyzed exo-, 3-O-, and 6-O-β-glucosides but not 20-O-β-glucoside and other glycosides of ginsenosides. Because of the novel specificity, this enzyme had the transformation pathways for ginsenosides: Rb₁ → Rd → F₂ → compound K, Rb₂ → compound O → compound Y, Rc → compound Mc₁ → compound Mc, Rg₃ → Rh₂ → aglycone protopanaxadiol (APPD), Rg₁ → F₁, and Rf → Rh₁ → aglycone protopanaxatriol (APPT). Under the optimum conditions, the enzyme converted 0.5 mM Rb₂, Rc, Rd, Rg₃, Rg₁, and Rf to 0.49 mM compound Y, 0.49 mM compound Mc, 0.47 mM compound K, 0.23 mM APPD, 0.49 mM F₁, and 0.44 mM APPT after 6 h, respectively.
authors.affiliation: Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Republic of Korea.
authors.forename: Gi-Woong
authors.initials: GW
authors.lastname: Lee
authors.forename: Mi-Hyun
authors.initials: MH
authors.lastname: Yoo
authors.forename: Kyung-Chul
authors.initials: KC
authors.lastname: Shin
authors.forename: Kyung-Cheol
authors.initials: KC
authors.lastname: Shin
authors.forename: Kyoung-Rok
authors.initials: KR
authors.lastname: Kim
authors.forename: Yeong-Su
authors.initials: YS
authors.lastname: Kim
authors.forename: Ki-Won
authors.initials: KW
authors.lastname: Lee
authors.forename: Deok-Kun
authors.initials: DK
authors.lastname: Oh
mesh_terms: D055162:Biocatalysis; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D036145:Ginsenosides / Q000737:chemistry* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010407:Penicillium / Q000737:chemistry / Q000201:enzymology*; D013379:Substrate Specificity; D001617:beta-Glucosidase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D036145:Ginsenosides; D001617:beta-Glucosidase