METHANE FERMENTATION OF FORMATE BY METHANOBACILLUS OMELIANSKII

Abstract

M. omelianskii ferments formate pri-marily by oxidation to CO2 and reduction to CH4. A limited intact incorporation of DCO2Na is demonstrable as CDH3 (6 mole % excess maximum) provided the competing formic dehydrogenase is inhibited with hypophosphite. Formate is inferior to CO2 as a precursor of CH4, but superior as a precursor of the B carbon of serine. A one-carbon transfer system may be related to the methane fermentation, but a direct involvement could not be demonstrated.