Methanogen

Methanogen

Methanogens are a group of microorganisms that produce methane as a metabolic byproduct in anoxic conditions. They are classified as archaea, a domain distinct from bacteria and eukaryotes. They are common in wetlands, where they are responsible for marsh gas, and in the digestive tracts of animals such as ruminants and humans, where they are responsible for the methane content of belching in ruminants and flatulence in humans.

Classification

Methanogens belong to the domain Archaea, which is distinct from Bacteria and Eukaryota. They are classified under the phylum Euryarchaeota, and further under the class Methanomicrobia.

Metabolism

Methanogens are unique among the archaea in that they metabolize by reducing carbon dioxide and other single-carbon compounds to methane, giving off energy. They also use a range of substrates to produce methane, including hydrogen, carbon dioxide, formate, methanol, methylamines, dimethyl sulfide, and acetate.

Ecology

Methanogens play a vital role in anaerobic environments where they aid in the decomposition of organic material and in the production of methane. They are found in a variety of environments, including wetlands, ruminant digestive systems, and human gut flora.

Role in disease

While methanogens are not typically pathogenic, some studies have suggested a potential link between the presence of methanogens and diseases such as periodontitis and irritable bowel syndrome.

See also

• Anaerobic digestion
• Biogas
• Methanotroph