Archaeal and bacterial communities in three alkaline hot springs in Heart Lake Geyser Basin, Yellowstone National Park

A study of three alkaline hot springs in Yellowstone National Park's Heart Lake Geyser Basin revealed distinct microbial community structures shaped by temperature, with significant temporal variability. While bacterial populations remained stable over three years but varied by temperature—ranging from photosynthetic and moderately thermophilic at 44°C to non-photosynthetic thermophiles at 75°C—the archaeal communities showed more dynamic shifts. The 75°C spring exhibited dramatic changes, transitioning from ammonia-oxidizing Candidatus Nitrosocaldus in 2007 to almost exclusively Thermofilum or Candidatus Caldiarchaeum in 2009. Notably, the majority of sequences were dissimilar (≥10%) to known organisms, suggesting the presence of novel phylogenetic groups that warrant further cultivation efforts. The research employed small subunit (SSU) rRNA gene pyrosequencing to monitor these microbial communities over time.

Bowen De León, K., Gerlach, R., Peyton, B. M., & Fields, M. W. (2013). Archaeal and bacterial communities in three alkaline hot springs in Heart Lake Geyser Basin, Yellowstone National Park. Frontiers in Microbiology, 4. https://doi.org/10.3389/fmicb.2013.00330