title: 3,4-Dihydrocoumarin hydrolase with haloperoxidase activity from Acinetobacter calcoaceticus F46.
abstract: A novel lactonohydrolase, an enzyme that catalyzes the hydrolysis of 3,4-dihydrocoumarin, was purified 375-fold to apparent homogeneity, with a 22.7% overall recovery, from Acinetobacter calcoaceticus F46, which was isolated as a fluorene-assimilating micro-organism. The molecular mass of the native enzyme, as estimated by high-performance gel-permeation chromatography, is 56 kDa, and the subunit molecular mass is 30 kDa. The enzyme specifically hydrolyzes 3,4-dihydrocoumarin, and the Km and Vmax for 3,4-dihydrocoumarin are 0.806 mM and 4760 U.mg-1, respectively. The N-terminal and internal amino acid sequences of the enzyme show high similarity to those of bacterial non-heme haloperoxidases. The enzyme exhibits brominating activity with monochlorodimedon in the presence of H2O2 and 3, 4-dihydrocoumarin or an organic acid, such as acetate and n-butyrate.
authors.affiliation: Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Japan. kataoka@kais.kyoto-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kataoka
authors.forename: K
authors.initials: K
authors.lastname: Honda
authors.forename: S
authors.initials: S
authors.lastname: Shimizu
mesh_terms: D000144:Acids, Acyclic / Q000378:metabolism; D016954:Acinetobacter calcoaceticus / Q000201:enzymology*; D000595:Amino Acid Sequence; D001966:Bromine / Q000378:metabolism*; D003374:Coumarins / Q000737:chemistry / Q000378:metabolism*; D003512:Cyclohexanones / Q000378:metabolism; D004795:Enzyme Stability; D004950:Esterases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006867:Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D007783:Lactones / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010544:Peroxidases / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013057:Spectrum Analysis; D013237:Stereoisomerism; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D000144:Acids, Acyclic; D001966:Bromine; D003374:Coumarins; D003512:Cyclohexanones; D004950:Esterases; D006861:Hydrogen Peroxide; D006867:Hydrolases; D007783:Lactones; D010544:Peroxidases; C006991:chlorodimedone; C403749:3,4-dihydrocoumarin hydrolase; C026308:3,4-dihydrocoumarin