Kan Jinjun, Clingenpeel Scott, Dow Charles L, McDermott Timothy R, Macur Richard E, Inskeep William P, Nealson Kenneth H
Stroud Water Research Center, Avondale PA, USA.
DOE Joint Genome Institute, Walnut Creek CA, USA.
Front Microbiol. 2016 Feb 29;7:210. doi: 10.3389/fmicb.2016.00210. eCollection 2016.
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), SO4 (2-), 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.
黄石湖是美国最大的亚高山湖泊，蕴藏着丰富多样的细菌和古菌。使用遥控水下机器人（ROV）从该湖不同位置的表层光合区、深层混合区和喷口流体中采集了不同粒径的水样（0.1 - 0.8、0.8 - 3.0和3.0 - 20μm）。实时荧光定量PCR分析表明，细菌在自由生活微生物中占主导地位，细菌与古菌的比例从4037:1（地表水）到25:1（喷口水）不等。利用454 - FLX测序技术对16S rRNA基因的V1和V2区域进行了总共662,302次焦磷酸测序读数，以此评估微生物种群结构（包括细菌和古菌）。非度量多维尺度分析（NMDS）表明，该湖自由生活的古菌和细菌从表层到深层喷口存在强烈的空间分布模式。除了pH值外，与喷口相关的主要地球化学成分，包括CH₄、CO₂、H₂、溶解无机碳（DIC）、溶解有机碳（DOC）、SO₄²⁻、O₂和金属，可能是微生物种群结构的主要驱动因素，然而，湖泊中发生的混合事件也影响了分布模式。不同粒径组分中存在不同的细菌和古菌，较大粒径组分包含与颗粒相关的微生物（> 3μm），并且与自由生活的微生物（<0.8μm）相比，预测的操作分类单元丰富度和微生物多样性（属水平）更高。我们的研究首次尝试解决黄石湖细菌和古菌的空间分布问题，我们的结果突出了古菌和细菌对氢、碳、氮和硫的水文地球化学相关代谢的不同贡献。
