Capnophile

Capnophiles are extremophile microorganisms which thrive in the presence of high concentrations of carbon dioxide, or which require the presence of carbon dioxide to survive.

Capnophiles are found in environments such as the stomachs of ruminant animals. One example, Mannheimia succiniciproducens, is known to fix carbon dioxide and produce succinic acid.

Another example of a capnophile is the Gram-negative Aggregatibacter spp. found in the mouth. Aggregatibacter actinomycetemcomitans is one of the causes of aggressive juvenile periodontitis.