Recent findings highlight the role of the human gut microbiota in various disorders. For example, atherosclerosis frequently seems to be the consequence of gut microbiota–derived metabolism of some dietary components. Pharmabiotics (i.e., live/dead microbes and microbe-derived substances) and probiotics (live microorganisms with a health benefit when administered in adequate amounts) are a means to counteract these deleterious effects. Among the latter, microbes now being used or, being currently developed, are bacteria and eukaryotes (yeasts), so omitting the third domain of life—the archaea, despite their unique properties that could be of great interest to human health. Here, we promote the idea that some specific archaea are potential next-generation probiotics. This is based on an innovative example of the bioremediation of a gut microbial metabolite. Indeed, besides the fact that they are archaea (i.e. originating from a domain of life from which no pathogens of humans/animals/plants are currently known), they are rationally selected based on (i) being naturally human-hosted, (ii) having a unique metabolism not performed by other human gut microbes, (iii) depleting a deleterious atherogenic compound generated by the human gut microbiota and (iv) generating a health inert gas.
Part of the book: Archaea