State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Appl Environ Microbiol. 2010 Nov;76(21):7171-80. doi: 10.1128/AEM.00832-10. Epub 2010 Sep 17.
The role of bacteria in the occasional emergence of red water, which has been documented worldwide, has yet to be determined. To better understand the mechanisms that drive occurrences of red water, the bacterial community composition and the relative abundance of several functional bacterial groups in a water distribution system of Beijing during a large-scale red water event were determined using several molecular methods. Individual clone libraries of the 16S rRNA gene were constructed for three red water samples and one sample of normal water. Beta-, Alpha-, and Gammaproteobacteria comprised the major bacterial communities in both red water and normal water samples, in agreement with previous reports. A high percentage of red water clones (25.2 to 57.1%) were affiliated with or closely related to a diverse array of iron-oxidizing bacteria, including the neutrophilic microaerobic genera Gallionella and Sideroxydans, the acidophilic species Acidothiobacillus ferrooxidans, and the anaerobic denitrifying Thermomonas bacteria. The genus Gallionella comprised 18.7 to 28.6% of all clones in the three red water libraries. Quantitative real-time PCR analysis showed that the 16S rRNA gene copy concentration of Gallionella spp. was between (4.1 ± 0.9) × 10⁷ (mean ± standard deviation) and (1.6 ± 0.3) × 10⁸ per liter in red water, accounting for 13.1% ± 2.9% to 17.2% ± 3.6% of the total Bacteria spp. in these samples. By comparison, the percentages of Gallionella spp. in the normal water samples were 0.1% or lower (below the limit of detection), suggesting an important role of Gallionella spp. in the formation of red water.
细菌在全球范围内偶尔出现的“红水”现象中的作用尚未确定。为了更好地了解导致“红水”出现的机制，采用多种分子方法，测定了北京某供水管网在一次大规模“红水”事件期间，其水样中细菌群落组成和几种功能细菌类群的相对丰度。对 3 个“红水”水样和 1 个正常水样的 16S rRNA 基因进行了克隆文库构建。β-、α-和γ-变形菌门构成了“红水”和正常水样中的主要细菌群落，这与以往的报道一致。高比例的“红水”克隆（25.2%至 57.1%）与多种铁氧化菌密切相关或隶属于这些菌，包括需氧兼性微好氧的节杆菌属和亚铁氧化硫杆菌属、嗜酸的氧化亚铁硫杆菌以及厌氧反硝化的 Thermomonas 菌。三个“红水”文库中，节杆菌属占所有克隆的 18.7%至 28.6%。实时定量 PCR 分析显示，节杆菌属的 16S rRNA 基因拷贝数浓度在“红水”中为（4.1±0.9）×10⁷（平均值±标准差）至（1.6±0.3）×10⁸ 拷贝/升，占这些样品中总细菌属的 13.1%±2.9%至 17.2%±3.6%。相比之下，节杆菌属在正常水样中的百分比为 0.1%或更低（低于检测限），表明节杆菌属在“红水”的形成中起着重要作用。
