title: Purification and characterization of glycyrrhetic acid mono-glucuronide beta-D-glucuronidase in Eubacterium sp. GLH.
abstract: Glycyrrhetic acid mono-glucuronide (GAMG), 1-(18beta-glycyrrhet-3-yl)-beta-D-glucopyranuroic acid, was hydrolyzed to glycyrrhetic acid (GA) by GAMG beta-D-glucuronidase in Eubacterium sp. GLH from human intestinal bacteria. The enzyme had an optimum pH of 5.0 and was purified from a crude extract by Butyl Toyopearl 650 S, Toyopearl HW-55 S, Hydroxyapatite and DEAE-Toyopearl 650 M column chromatography. The purified enzyme showed a specific activity of 495 nmol/min/mg protein and a single band on Coomassie brilliant blue staining and a molecular weight of about 43 kDa on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The apparent molecular weight was 49.5 kDa, as estimated by Toyopearl HW-55 S column chromatography. Also, the enzyme seemed to have a sulfhydryl group(s) in its active site with a Km value of 77 x 10(-3) M.
authors.affiliation: Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Akao
mesh_terms: D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D005051:Eubacterium / Q000201:enzymology* / Q000302:isolation & purification; D005966:Glucuronidase / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006034:Glycyrrhetinic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D008970:Molecular Weight