Methane monooxygenase catalyzed oxygenation of 1,1-dimethylcyclopropane. Evidence for radical and carbocationic intermediates.

@article{Ruzicka1990MethaneMC,
  title={Methane monooxygenase catalyzed oxygenation of 1,1-dimethylcyclopropane. Evidence for radical and carbocationic intermediates.},
  author={F. Ruzicka and D. S. Huang and M. Donnelly and P. Frey},
  journal={Biochemistry},
  year={1990},
  volume={29 7},
  pages={
          1696-700
        }
}
Methane monooxygenase catalyzes the oxygenation of 1,1-dimethylcyclopropane in the presence of O2 and NADH to (1-methylcyclopropyl)methanol (81%), 3-methyl-3-buten-1-ol (6%), and 1-methyl-cyclobutanol (13%). Oxygenation by 18O2 using the purified enzyme proceeds with incorporation of 18O into the products. Inasmuch as methane monooxygenase catalyzes the insertion of O from O2 into a carbon-hydrogen bond of alkanes, (1-methylcyclopropyl)methanol appears to be a conventional oxygenation product… Expand
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The hydroxylase component of methane monooxygenase (EC 1.25), which catalyzes the oxidation of methane to methanol, has been studied by visible, electron spin resonance and X-ray spectroscopies and generates ESR-detectable states that appear to emanate from mixed-valence binuclear sites. Expand
Oxidation of Hydrocarbons by Methane Monooxygenases from a Variety of Microbes
Publisher Summary Methane monooxygenase is the enzyme responsible for the initial oxygenation of methane to methanol. The methanotrophs (methane-oxidizing bacteria) are divided into two typesExpand
Methane monooxygenase from Methylosinus trichosporium OB3b. Purification and properties of a three-component system with high specific activity from a type II methanotroph.
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The data presented here provide the first evidence based on catalysis that the site of the monooxygenation reaction is located on the hydroxylase, and implies a new mechanism for the generation of highly reactive oxygen capable of insertion into unactivated carbon-hydrogen bonds. Expand
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Abstract ESR spectroscopy of protein A, proposed to be the oxygenase component of the methane monooxygenase (methane, NAD(P)H:oxygen oxidoreductase (hydroxylating), EC 1.14.13.25) from MethylococcusExpand
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Methylococcus capsulatus (Bath) possesses a multi-component methane monooxygenase which catalyzes in vivo the conversion of methane to methanol. Component A of this enzyme system, believed to be theExpand
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TLDR
A purification protocol is described here for the previously uncharacterized protein B of the soluble methane monooxygenase from the obligate methanotroph Methylococcus capsulatus (Bath), possessing the capacity to convert the enzyme from an oxidase to an oxygenase. Expand
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TLDR
The results showed that the oxygen in methanol was derived exclusively from gaseous oxygen in both micro-organisms, and control experiments confirmed that there was negligible incorporation of the oxygen atom from water into meethanol. Expand
Small-ring compounds—XXIX A reinvestigation of the solvolysis of cyclopropylcarbinyl chloride in aqueous ethanol. Isomerization of cyclopropylcarbinol
The solvolysis of cyclopropylcarbinyl chloride in 80% ethanol is attended by substantial rearrangement—not only do the solvolysis products include cyclobutyl and allylcarbinyl alcohols and ethylExpand
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