Which among the following microbe helps in the prodcuction of biogas ?

Methanobacterium

Bacteria, which grow anaerobically on cellulosic material, produce large amount of methane along with CO₂ and H₂ . These bacteria are collectively called methanogens, and one such common bacterium is Methanobacterium. These bacteria are commonly found in the anaerobic sludge during sewage treatment. These bacteria are also present in the rumen (a part of stomach) of cattle.