Shehzad Ahmed, Liu Jiwen, Yu Min, Qismat Shakeela, Liu Jingli, Zhang Xiao-Hua
College of Marine Life Sciences, Ocean University of China.
Microbes Environ. 2016 Jun 25;31(2):111-20. doi: 10.1264/jsme2.ME15140. Epub 2016 May 14.
Over the past few decades, anammox bacteria have been recognized as key players that contribute significantly to the release of large amounts of nitrogen in the global marine nitrogen cycle. In the present study, the diversity, community composition, and abundance of anammox bacteria from the sediments of four diverse regions in the north marginal seas in China were determined via clone library construction and a quantitative PCR analysis. The clone libraries retrieved by the 16S rRNA gene and Hzo gene markers indicated that "Candidatus Scalindua" was the predominant group throughout the sites examined. The 16S rRNA gene clone libraries revealed exceptional diversity by identifying two potential novel anammox clades, as evidenced by the high sequence similarities between these two clades and known anammox genera, and their unique phylogenetic positions with high bootstrap values. However, their potential roles in the anammox reaction need to be validated. Six novel members of Planctomycetes, divergent from the known genera of anammox bacteria, were also detected. A phylogenetic analysis by Hzo protein sequences revealed the existence of two known genera, i.e., "Candidatus Jettenia" and "Candidatus Anammoxoglobus", which are rarely captured from marine sediments. Among all ecological parameters investigated, the distribution patterns and composition of anammox bacteria were found to be influenced by salinity, total organic matter, and temperature. The abundance of the anammox bacterial 16S rRNA gene from the sites examined ranged between 3.95×10(5) and 9.21×10(5) copies g(-1) wet sediment and positively correlated with the median size of the sediment sample.
在过去几十年里，厌氧氨氧化细菌被认为是全球海洋氮循环中大量氮释放的关键参与者。在本研究中，通过构建克隆文库和定量PCR分析，确定了中国北方边缘海四个不同区域沉积物中厌氧氨氧化细菌的多样性、群落组成和丰度。通过16S rRNA基因和Hzo基因标记检索到的克隆文库表明，“候选斯卡林杜亚菌属”是所有检测位点的优势菌群。16S rRNA基因克隆文库通过鉴定两个潜在的新型厌氧氨氧化进化枝揭示了异常的多样性，这两个进化枝与已知厌氧氨氧化菌属之间的高序列相似性以及它们具有高自展值的独特系统发育位置证明了这一点。然而，它们在厌氧氨氧化反应中的潜在作用需要得到验证。还检测到了六个与已知厌氧氨氧化细菌属不同的浮霉菌门新成员。通过Hzo蛋白序列进行的系统发育分析揭示了两个已知菌属的存在，即“候选杰特尼亚菌属”和“候选厌氧氨氧化球杆菌属”，它们很少从海洋沉积物中捕获到。在所有调查的生态参数中，发现厌氧氨氧化细菌的分布模式和组成受盐度、总有机质和温度的影响。所检测位点的厌氧氨氧化细菌16S rRNA基因丰度在3.95×10(5)至9.21×10(5)拷贝 g(-1)湿沉积物之间，并且与沉积物样品的中值大小呈正相关。
