Isolation and Characterization of Methanobacterium Ruminantium N. Sp

Numerous investigators, starting with Reiset (1863), have demonstrated that much methane is formed in the rumen, suggesting that methano-genic bacteria are abundant in this environment. Information on their nature is sparse. Beijer (1952) detected Methanosarcina in the goat rumen, and Opperman et al. (1957) demonstrated Methano-bacterium formicicum and a methanogenic acetate-utilizer in cattle, but the abundance of these organisms was not determined. The importance of the methanogenic bacteria in the rumen and the fact that they are the chief known bacterial component that has eluded pure culture, stimulated an attempt to determine their numbers in bovine rumen contents and to isolate the predominant types in pure culture. DEVELOPMENT OF A SUITABLE TECHNIQUE A mixture of 80 per cent hydrogen and 20 per cent carbon dioxide was employed as substrate. The final percentage composition (w/v) of the other ingredients of the medium was K2HPO4,