title: Performance of D-amino acid oxidase in presence of ionic liquids.
abstract: The activity and stability of free and immobilized D-amino acid oxidase (DAAO, EC 1.4.3.3) from Trigonopsis variabilis CBS 4095 in different water-soluble and water-insoluble ionic liquids (ILs) as well as in organic solvents were studied for comparison. The most promising ILs ([BMIM][BF(4)] and [MMIM][MMPO(4)]) were investigated in detail. The kinetic parameters (v(max) = 187 nkat/g dry weight, K(M) = 1.38 mM) with D-phenylalanine as substrate were calculated in 40% [BMIM][BF(4)]. Bioconversions of D/L-phenylalanine in 40% [BMIM][BF(4)] and 20% [MMIM][MMPO(4)] on a 3 ml scale using immobilized DAAO were performed by addition of free catalase from Micrococcus lysodeikticus. After total conversion of substrate in presence of 20% [MMIM][MMPO(4)] the residual activity of the immobilized DAAO was 79% and 100% of the free catalase.
authors.affiliation: Department of Biotechnology, Institute of Food Technology, University of Hohenheim, Stuttgart, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Lutz-Wahl
authors.forename: E-M
authors.initials: EM
authors.lastname: Trost
authors.forename: B
authors.initials: B
authors.lastname: Wagner
authors.forename: A
authors.initials: A
authors.lastname: Manns
authors.forename: L
authors.initials: L
authors.lastname: Fischer
mesh_terms: D001711:Biotransformation; D002374:Catalase / Q000032:analysis / Q000494:pharmacology; D002384:Catalysis; D003605:D-Amino-Acid Oxidase / Q000737:chemistry* / Q000145:classification* / Q000378:metabolism*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized; D005240:Feasibility Studies; D007700:Kinetics; D008837:Micrococcus / Q000145:classification / Q000201:enzymology; D009930:Organic Chemicals / Q000737:chemistry* / Q000145:classification; D004718:Saccharomycetales / Q000201:enzymology; D012995:Solubility; D012997:Solvents / Q000737:chemistry / Q000145:classification; D013379:Substrate Specificity; D014867:Water / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D009930:Organic Chemicals; D012997:Solvents; D014867:Water; D002374:Catalase; D003605:D-Amino-Acid Oxidase