Geochemistry and mixing drive the spatial distribution of free-living archaea and bacteria in Yellowstone Lake

350 210 Stroud Water Research Center

Kan, J., S. Clingenpeel, C.L. Dow, T.R. McDermott, R.E. Macur, W.P. Inskeep, and K.H. Nealson. 2016. Frontiers in Microbiology 7(210):1–13.

doi: 10.3389/fmicb.2016.00210


Yellowstone Lake, the largest subalpine lake in the United States, harbors great novelty and diversity of Bacteria and Archaea. Size-fractionated water samples (0.1–0.8, 0.8–3.0, and 3.0–20 μm) were collected from surface photic zone, deep mixing zone, and vent fluids at different locations in the lake by using a remotely operated vehicle (ROV). Quantification with real-time PCR indicated that Bacteria dominated free-living microorganisms with Bacteria/Archaea ratios ranging from 4037:1 (surface water) to 25:1 (vent water). Microbial population structures (both Bacteria and Archaea) were assessed using 454-FLX sequencing with a total of 662,302 pyrosequencing reads for V1 and V2 regions of 16S rRNA genes. Non-metric multidimensional scaling (NMDS) analyses indicated that strong spatial distribution patterns existed from surface to deep vents for free-living Archaea and Bacteria in the lake. Along with pH, major vent-associated geochemical constituents including CH4, CO2, H2, DIC (dissolved inorganic carbon), DOC (dissolved organic carbon), SO42-, O2 and metals were likely the major drivers for microbial population structures, however, mixing events occurring in the lake also impacted the distribution patterns. Distinct Bacteria and Archaea were present among size fractions, and bigger size fractions included particle-associated microbes (> 3 μm) and contained higher predicted operational taxonomic unit richness and microbial diversities (genus level) than free-living ones (<0.8 μm). Our study represents the first attempt at addressing the spatial distribution of Bacteria and Archaea in Yellowstone Lake, and our results highlight the variable contribution of Archaea and Bacteria to the hydrogeochemical-relevant metabolism of hydrogen, carbon, nitrogen, and sulfur.

Give the Gift of Fresh Water

As you give thanks for the gifts in your life, we invite you to give the gift of water. Clean drinking water, good health, happy trout, productive soil, clean air, the simple joys of swimming, boating, fishing — our healthy freshwater ecosystems make these and so many other things possible.

Your donation today will help preserve and protect
the future of fresh water.