Methanol dissimilation in Desulfotomaculum kuznetsovii

The enzymes involved in methanol degradation by Desulfotomaculum kuznetsovii, a thermophilic, methanol utilizing sulfate reducer were studied. Low NAD-dependent and dye-linked alcohol dehydrogenase activities were detected with methanol in cell free extracts of D. kuznetsovii grown on methanol. However, activities with ethanol as electron donor were 10 times higher. The alcohol dehydrogenase from D. kuznetsovii was partially purified and characterized. Methyltransferase activity with tetrahydrofolate as acceptor was not detected. Cells grown on different alcohols showed different protein patterns on 2D-PAGE, indicating that the enzymes were induced by methanol. However, we were not able to isolate solitary spots for N-terminal amino acid sequence determination. Our results indicate that an alcohol dehydrogenase is active with methanol in D. kuznetsovii, although activities are low. We cannot conclude if this enzyme is responsible for methanol oxidation in D. kuznetsovii. However, this is the first report concerning methanol metabolism in a thermophilic Desulfotomaculum species.