Infectious Disease Compendium

Archaea

Microbiology

The third domain of life, along with Bacteria and Eukarya.

Methanobrevibacter smithii, a methanogen is the most common archaean in the human gut, about ten% of all prokaryotes.

Epidemiologic Risks

They are everywhere, including in us (PubMed). Most cannot be grown. Perhaps the oldest form of life.

Syndromes

"Currently, there is no substantial evidence supporting the pathogenic properties of the Archaea. The best they can do is to seize the opportunity created by pathological processes and occupy the microenvironments suitable for this type of anaerobic hydrogenotrophic metabolism. These niches, however, can also be occupied by other microbiota with similar metabolic properties (PubMed)."

Although there is no end of speculation (PubMed) and investigations into the role of Archaea in human disease, these investigations are still early and far from definitive.

See the Curious Case below.

Treatment

Notes

Per the Wikipedia: "It has been proposed that the archaea evolved from gram-positive bacteria in response to antibiotic selection pressure. This is suggested by the observation that archaea are resistant to a wide variety of antibiotics that are primarily produced by gram-positive bacteria, and that these antibiotics primarily act on the genes that distinguish archaea from bacteria. The proposal is that the selective pressure towards resistance generated by the gram-positive antibiotics was eventually sufficient to cause extensive changes in many of the antibiotics' target genes, and that these strains represented the common ancestors of present-day Archaea.[74] The evolution of Archaea in response to antibiotic selection, or any other competitive selective pressure, could also explain their adaptation to extreme environments (such as high temperature or acidity) as the result of a search for unoccupied niches to escape from antibiotic-producing organisms (Wikipedia)." It makes you wonder what antibiotics are doing today to bacteria.

Curious Cases

Relevant links to my Medscape blog

Ignorance is Bliss. It is why I am so happy.

Last update: 01/02/20