Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
Department of Micro- and Nanotechnology, Technical University of Denmark, Kgs Lyngby 2800, Denmark.
Environ Microbiol. 2018 Mar;20(3):1002-1015. doi: 10.1111/1462-2920.14033. Epub 2018 Jan 5.
The recent discovery of completely nitrifying Nitrospira demands a re-examination of nitrifying environments to evaluate their contribution to nitrogen cycling. To approach this challenge, tools are needed to detect and quantify comammox Nitrospira. We present primers for the simultaneous quantification and diversity assessement of both comammox Nitrospira clades. The primers cover a wide range of comammox diversity, spanning all available high quality sequences. We applied these primers to 12 groundwater-fed rapid sand filters, and found comammox Nitrospira to be abundant in all filters. Clade B comammox comprise the majority (∼75%) of comammox abundance in all filters. Nitrosomonadaceae were present in all filters, although at low abundance (mean = 1.8%). Ordination suggests that temperature impacts the structure of nitrifying communities, and in particular that increasing temperature favours Nitrospira. The nitrogen content of the filter material, sulfate concentration and surface ammonium loading rates shape the structure of the comammox guild in the filters. This work provides an assay for simultaneous detection and diversity assessment of clades A and B comammox Nitrospira, expands our current knowledge of comammox Nitrospira diversity and demonstrates a key role for comammox Nitrospira in nitrification in groundwater-fed biofilters.
最近发现完全硝化的 Nitrospira 要求重新审视硝化环境，以评估它们对氮循环的贡献。为了应对这一挑战，需要有工具来检测和量化 comammox Nitrospira。我们提出了用于同时定量和多样性评估两种 comammox Nitrospira 丛的引物。这些引物涵盖了广泛的 comammox 多样性，涵盖了所有可用的高质量序列。我们将这些引物应用于 12 个地下水驱动的快速砂滤器中，发现所有滤器中都存在丰富的 comammox Nitrospira。B 丛的 comammox 构成了所有滤器中 comammox 丰度的大部分（约 75%）。所有滤器中都存在 Nitrosomonadaceae，但丰度较低（平均为 1.8%）。排序表明温度会影响硝化群落的结构，特别是温度升高有利于 Nitrospira。滤料中的氮含量、硫酸盐浓度和表面氨负荷率塑造了滤器中 comammox 菌群的结构。这项工作提供了一种用于同时检测和多样性评估 A 丛和 B 丛 comammox Nitrospira 的方法，扩展了我们对 comammox Nitrospira 多样性的现有认识，并证明了 comammox Nitrospira 在地下水驱动的生物滤器中硝化作用中的关键作用。
