title: Butane monooxygenase of 'Pseudomonas butanovora': purification and biochemical characterization of a terminal-alkane hydroxylating diiron monooxygenase.
abstract: Butane monooxygenase (sBMO) has been purified to homogeneity from the Gram-negative beta-proteobacterium 'Pseudomonas butanovora' and confirmed to be a three-component diiron monooxygenase system. The reconstituted enzyme complex oxidized C(3)-C(6) linear and branched aliphatic alkanes, which are growth substrates for 'P. butanovora'. The sBMO complex was composed of an iron-containing hydroxylase (BMOH), a flavo-iron sulfur-containing NADH-oxidoreductase (BMOR) and a small regulatory component protein (BMOB). The physical characteristics of sBMO were remarkably similar to the sMMO family of soluble multicomponent diiron monooxgenases. However, the catalytic properties of sBMO were quantitatively different in regard to inactivation in the presence of substrate and product distribution. BMOH was capable of ethene oxidation when supplied with H(2)O(2) and ethene (known as the peroxide shunt), but this activity was at least three orders of magnitude less than that observed for the hydroxylase of sMMO of Methylosinus trichosporium OB3b. BMOH and BMOR were efficient in the oxidation of ethene in the absence of BMOB with regard to rate of reaction and product yield. Regiospecificity of sBMO was strongly biased towards primary hydroxylation, with > or = 80 % of the hydroxylations occurring at the terminal carbon atom.
authors.affiliation: Department of Botany and Plant Pathology, 2082 Cordley Hall, Oregon State University, Corvallis, OR 97331-2902, USA.
authors.forename: Bradley L
authors.initials: BL
authors.lastname: Dubbels
authors.affiliation: Department of Botany and Plant Pathology, 2082 Cordley Hall, Oregon State University, Corvallis, OR 97331-2902, USA.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Sayavedra-Soto
authors.affiliation: Department of Botany and Plant Pathology, 2082 Cordley Hall, Oregon State University, Corvallis, OR 97331-2902, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Arp
mesh_terms: D000473:Alkanes / Q000378:metabolism; D002073:Butanes / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D020536:Enzyme Activators / Q000494:pharmacology; D004795:Enzyme Stability / Q000187:drug effects; D005030:Ethylenes / Q000378:metabolism; D038181:FMN Reductase / Q000302:isolation & purification; D006861:Hydrogen Peroxide / Q000378:metabolism; D007501:Iron / Q000494:pharmacology*; D020602:Methylosinus trichosporium / Q000201:enzymology; D006899:Mixed Function Oxygenases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D010084:Oxidation-Reduction; D021122:Protein Subunits; D011549:Pseudomonas / Q000201:enzymology* / Q000378:metabolism; D013057:Spectrum Analysis; D013379:Substrate Specificity
chemical_list: D000473:Alkanes; D002073:Butanes; D020536:Enzyme Activators; D005030:Ethylenes; D021122:Protein Subunits; C046888:butane; C036216:ethylene; D006861:Hydrogen Peroxide; D007501:Iron; D006899:Mixed Function Oxygenases; D038181:FMN Reductase