journals.asm.org
Why are archaea not pathogenic? A hypothesis based on metabolism-habitat covariation | mBio
Pathogenicity—the ability to cause infectious disease—is widespread among bacteria
and eukaryotes but conspicuously absent from archaea, the third domain of life. To
understand why archaea are non-pathogenic, we performed comparative analyses of thousands
of bacterial and archaeal isolates. We found that the absence of pathogenic archaea
can be explained by a combination of metabolic and environmental factors. Specifically,
archaea living within eukaryotic, multicellular hosts lack a metabolic capability
correlated with pathogenicity—chemo-organo-heterotrophy—whereas those possessing this
metabolism typically live under extreme conditions, such as high temperature, and
therefore lack the environmental opportunity to interact with eukaryotic hosts. These
findings advance our understanding of microbes by revealing important links between
their metabolism, habitats, and pathogenicity.
