Soluble Methane Mono-oxygenase of Methylococcus capsulatus (Bath)
نویسندگان
چکیده
1. Methane mono-oxygenase of Methylococcus capsulatus (Bath) catalyses the oxidation of various substituted methane derivatives including methanol. 2. It is a very non-specific oxygenase and, in some of its catalytic properties, apparently resembles the analogous enzyme from Methylomonas methanica but differs from those found in Methylosinus trichosporium and Methylomonas albus. 3. CO is oxidized to CO2. 4. C1-C8 n-alkanes are hydroxylated, yielding mixtures of the corresponding 1and 2-alcohols; no 3or 4-alcohols are formed. 5. Terminal alkenes yield the corresponding 1,2-epoxides. cisor trans-but-2ene are each oxidized to a mixture of 2,3-epoxybutane and but-2-en-l-ol with retention of the cis or trans configuration in both products; 2-butanone is also formed from cis-but-2ene only. 6. Dimethyl ether is oxidized. Diethyl ether undergoes sub-terminal oxidation, yielding ethanol and ethanal in equimolar amounts. 7. Methane mono-oxygenase also hydroxylates cyclic alkanes and aromatic compounds. However, styrene yields only styrene epoxide and pyridine yields only pyridine N-oxide. 8. Of those compounds tested, only NADPH can replace NADH as electron donor.
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