Detection and localization of two hydrogenases in Methylococcus capsulatus (Bath) and their potential role in methane metabolism.
Methylococcus capsulatus (Bath) was shown to contain two distinct hydrogenases, a soluble hydrogenase and a membrane-bound hydrogenase. This is the first report of a membrane-bound hydrogenase in methanotrophs. Both enzymes were expressed apparently constitutively under normal growth conditions. The soluble hydrogenase was capable of reducing NAD(+) with molecular hydrogen. The activities of both soluble and particulate methane monooxygenases could be driven by molecular hydrogen. This confirmed that molecular hydrogen could be used as a source of reducing power for methane oxidation. Hydrogen-driven methane monooxygenase activities tolerated elevated temperatures and moderate oxygen concentrations. The significance of these findings for biotechnological applications of methanotrophs is discussed.
Hanczár
Tímea
T
Department of Biotechnology, University of Szeged, Hungary.
Csáki
Robert
R
Bodrossy
Levente
L
Murrell
J Colin
JC
Kovács
Kornél L
KL
D006859:Hydrogen / Q000378:metabolism; D006864:Hydrogenase / Q000302:isolation & purification*; D008697:Methane / Q000378:metabolism; D020619:Methylococcus capsulatus / Q000201:enzymology*; D010088:Oxidoreductases / Q000302:isolation & purification; D010105:Oxygenases / Q000378:metabolism
D006859:Hydrogen; D010088:Oxidoreductases; C043296:nickel-iron hydrogenase; C021376:hydrogen dehydrogenase; D006864:Hydrogenase; D010105:Oxygenases; C021555:methane monooxygenase; D008697:Methane