Methane monooxygenase oxidized

Fox BG, Bomeman JG, Wackett LP, et al. 1990. Haloalkane oxidation by the soluble methane monooxygenase irom Methylosinus trichosporium OB3b Mechanistic and environmental implications. Biochemistry 29 6419-6427. 

Patel RN, CT Hou, Al Laskin, A Felix (1982) Microbial oxidation of hydrocarbons properties of a soluble methane monooxygenase from a facultative methane-utilizing organism, Methylobacterium sp. strain CRL-26. Appl Environ Microbiol 44 1130-1137. 

In some cases, microorganisms can transform a contaminant, but they are not able to use this compound as a source of energy or carbon. This biotransformation is often called co-metabolism. In co-metabolism, the transformation of the compound is an incidental reaction catalyzed by enzymes, which are involved in the normal microbial metabolism.33 A well-known example of co-metabolism is the degradation of (TCE) by methanotrophic bacteria, a group of bacteria that use methane as their source of carbon and energy. When metabolizing methane, methanotrophs produce the enzyme methane monooxygenase, which catalyzes the oxidation of TCE and other chlorinated aliphatics under aerobic conditions.34 In addition to methane, toluene and phenol have been used as primary substrates to stimulate the aerobic co-metabolism of chlorinated solvents. 

Metalloenzymes with non-heme di-iron centers in which the two irons are bridged by an oxide (or a hydroxide) and carboxylate ligands (glutamate or aspartate) constitute an important class of enzymes. Two of these enzymes, methane monooxygenase (MMO) and ribonucleotide reductase (RNR) have very similar di-iron active sites, located in the subunits MMOH and R2 respectively. Despite their structural similarity, these metal centers catalyze very different chemical reactions. We have studied the enzymatic mechanisms of these enzymes to understand what determines their catalytic activity [24, 25, 39-41]. 

Oremland et al. [136] subsequently demonstrated that methane-oxidizing bacteria also had the capacity to co-oxidize methyl bromide by methane monooxygenase produced during the oxidation of methane to methanol. They also showed that methanotrophic soils that had a high capacity to oxidize methane degraded14C-labeled methyl bromide to 14C02. 

OXYGEN, OXIDES 0X0 ANIONS METHANE MONOOXYGENASE Methanol, autoprotolysis constant, AUTOPROTOLYSIS METHANOL DEHYDROGENASE... 

Itoh et al. used Cu yd-diketiminato complexes with general formula 4, and their reactivity has been described as a functional model for pMMO (particulate methane monooxygenase). Initially, the Hgands were reacted with both Cu and Cu precursors, with a variety of species formed, depending on the specific conditions employed [111, 112]. It was then shown that both Cu and Cu complexes ultimately led to bis(/z-oxo)(Cu )2 species upon reaction with O2 and H2O2, respectively. Use of these Cu complexes as the pre-catalysts for the oxidation of alkanes (cyclohexane and adamantane) in the presence of H2O2 resulted in low yields ( 20%). 

Hu, Z. Gorun, S. M. Methane monooxygenase models, Biomimetic Oxidations Catalyzed by Transition Metal Complexes , Ed. Meunier, B. Imperial College Press London, 2000, pp. 269—307. 

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