Exo-beta-D-glucuronidase from the fungus Kobayasia nipponica.
The occurrence of three forms, I, II, and III, of exo-beta-D-glucuronidase of the fungus Kobayasia nipponica was demonstrated. These three forms were purified 1,905-fold, 857-fold, and 357-fold, respectively. Forms I, II, and III of exo-beta-D-glucuronidase behaved differently on heparin-Sepharose chromatography, and differed in optimum pH (3.5, 3.2, and 2.6, respectively), pH-stability, Km (0.22, 0.16, and 0.13 mM, respectively), and Vmax (V) values. Their molecular weights, as estimated by gel filtration through Sephacryl S-200, were all 70,000; polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate gave a value of 72,000. These three forms were very active towards 1-4 linked beta-D-glucuronans, (Formula: see text) and (Formula: see text), but weak or inactive towards protuberic acid and several glycosaminoglycans.
D001487:Basidiomycota / Q000201:enzymology*; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003300:Copper / Q000494:pharmacology; D004355:Drug Stability; D004591:Electrophoresis, Polyacrylamide Gel; D005966:Glucuronidase / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008970:Molecular Weight; D011134:Polysaccharides / Q000378:metabolism*
D011134:Polysaccharides; C040159:protuberic acid; D003300:Copper; D005966:Glucuronidase