Toluene-4-monooxygenase, a three-component enzyme system that catalyzes the oxidation of toluene to p-cresol in Pseudomonas mendocina KR1.
Pseudomonas mendocina KR1 grows on toluene as a sole carbon and energy source. A multicomponent oxygenase was partially purified from toluene-grown cells and separated into three protein components. The reconstituted enzyme system, in the presence of NADH and Fe2+, oxidized toluene to p-cresol as the first detectable product. Experiments with p-deutero-toluene led to the isolation of p-cresol which retained 68% of the deuterium initially present in the parent molecule. When the reconstituted enzyme system was incubated with toluene in the presence of 18O2, the oxygen in p-cresol was shown to be derived from molecular oxygen. The results demonstrate that P. mendocina KR1 initiates degradation of toluene by a multicomponent enzyme system which has been designated toluene-4-monooxygenase.
Whited
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GM
Center for Applied Microbiology, University of Texas, Austin 78712.
Gibson
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DT
D002848:Chromatography, DEAE-Cellulose; D002851:Chromatography, High Pressure Liquid; D003408:Cresols / Q000378:metabolism; D010105:Oxygenases / Q000502:physiology*; D011549:Pseudomonas / Q000378:metabolism*; D014050:Toluene / Q000378:metabolism*
D003408:Cresols; C032538:4-cresol; D014050:Toluene; D010105:Oxygenases; C068610:toluene-4-monooxygenase