title: Production, characterization and (co-)immobilization of dextranase from Penicillium aculeatum.
abstract: Fermentation kinetics of Penicillium aculeatum ATCC 10409 demonstrated that fungal growth and dextranase release are decoupled. Inoculation by conidia or mycelia resulted in identical kinetics. Two new isoenzymes of the dextranase were characterized regarding their kinetic constants, pI, MW, activation energy and stabilities. The larger enzyme was 3-fold more active (turnover number: 2,230 +/- 97 s(-1)). Pre-treatment of bentonite with H(2)O(2) did not affect adsorption characteristics of dextranase. Enzyme to bentonite ratios above 0.5:1 (w/w) resulted in a high conservation of activity upon adsorption. Furthermore, dextranase could be used in co-immobilizates for the direct conversion of sucrose into isomalto-oligosaccharides (e.g. isomaltose). Yields of co-immobilizates were 2-20 times that of basic immobilizates, which consist of dextransucrase without dextranase.
authors.affiliation: Department for Carbohydrate Technology, Institute for Technical Chemistry, Technical University Braunschweig, Hans-Sommer-Strasse 10, 38106, Braunschweig, Germany.
authors.forename: Frank A
authors.initials: FA
authors.lastname: Erhardt
authors.forename: Simon
authors.initials: S
authors.lastname: Stammen
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Jördening
mesh_terms: D000327:Adsorption; D001546:Bentonite / Q000493:pharmacokinetics*; D002850:Chromatography, Gel; D003910:Dextranase / Q000096:biosynthesis* / Q000378:metabolism*; D003911:Dextrans / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005285:Fermentation; D005964:Glucosyltransferases / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000493:pharmacokinetics; D007527:Isoenzymes / Q000096:biosynthesis / Q000378:metabolism; D007534:Isomaltose / Q000378:metabolism; D010407:Penicillium / Q000201:enzymology*; D012965:Sodium Chloride / Q000493:pharmacokinetics; D013395:Sucrose / Q000378:metabolism
chemical_list: D003911:Dextrans; D004800:Enzymes, Immobilized; D007527:Isoenzymes; D001546:Bentonite; D012965:Sodium Chloride; D013395:Sucrose; D007534:Isomaltose; D006861:Hydrogen Peroxide; D005964:Glucosyltransferases; C020025:dextransucrase; D003910:Dextranase