Nanoarchaeota, Their Sulfolobales Host, and Nanoarchaeota Virus Distribution across Yellowstone National Park Hot Springs

A groundbreaking discovery reveals the presence of Nanoarchaeota, obligate symbionts with reduced genomes, thriving in high-temperature (∼90°C), acidic (pH ≈ 2.5 to 3.0) hot springs within Yellowstone National Park (YNP). This finding challenges previous assumptions that Nanoarchaeota were exclusive to marine thermal vent environments. Single-cell genome analysis identified two nearly identical genomes, more closely related to the recently proposed Nanobsidianus stetteri from a neutral YNP hot spring than to the marine Nanoarchaeum equitans. The study employed community metagenomics and single-cell analysis, alongside catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH), to pinpoint Sulfolobales as their host species. Additionally, an integrated viral sequence within one Nanoarchaeota genome suggests a virus replicating within these symbionts, indicating a complex microbial ecosystem in YNP's acidic hot springs.

Munson-McGee, J. H., Field, E. K., Bateson, M., Rooney, C., Stepanauskas, R., & Young, M. J. (2015). Nanoarchaeota, Their Sulfolobales Host, and Nanoarchaeota Virus Distribution across Yellowstone National Park Hot Springs. Applied and Environmental Microbiology, 81(22), 7860–7868. https://doi.org/10.1128/aem.01539-15