高通量测序分析多种典型生境中厌氧氨氧化细菌的多样性分布特征

Diversity analysis of anaerobic ammonium-oxidizing bacteria in typical habitats by high throughput sequencing

摘要:

【背景】厌氧氨氧化过程是氮素循环过程的重要途径之一，在氮素循环中发挥重要作用。先前的研究已经证实了厌氧氨氧化细菌存在于多种生境中，但对其多样性分布还没有系统的研究。【目的】对厌氧氨氧化细菌在不同类型生境中的多样性分布规律进行深入分析，充分展示其在不同生境中的群落结构特点，并揭示多样性分布与环境因素之间的关系。【方法】在建立厌氧氨氧化细菌16S rRNA基因序列数据库的基础上，运用高通量测序技术分析其在不同生境中的多样性分布特征。【结果】厌氧氨氧化细菌在红树林、海湾和河口生境中的多样性水平较高，而污泥和红壤的多样性水平明显较低。系统发育分析表明，这些生境中的厌氧氨氧化细菌主要由Candidatus Brocadia、Ca. Scalindua和未明确分类地位的菌属组成；从河流到红树林生态系统，随着盐度的增加，厌氧氨氧化细菌的优势种属由Ca. Brocadia转变到Ca. Scalindua，相关性分析也表明了盐度是导致不同生境中厌氧氨氧化细菌群落结构差异的主要因素。【结论】不同生境中存在不同的厌氧氨氧化细菌种群结构，环境条件的差异影响了厌氧氨氧化细菌的种群分布和系统演化。

Abstract:

[Background] Anaerobic ammonium oxidation (Anammox) is one of the important processes of nitrogen cycling. Previous studies have confirmed that anaerobic ammonium-oxidizing bacteria existed in various habitats, but there is no comprehensive understanding about their ecological distribution. [Objective] In this paper, we analyzed the diversity distribution of anammox bacteria in multiple habitats. This study will demonstrate the characteristics of community structure of anammox bacteria in different habitats and will illuminate the relationship between diversity distribution and environmental factors. [Methods] Based on the established anammox bacterial 16S rRNA gene sequence database, high throughput sequencing technology was used to analyze the diversity distribution of anammox bacteria in different habitat. [Results] The diversity of anammox bacteria in mangrove, bay and estuary habitats were relatively higher than that of sludge and red soil. Anammox bacteria in these habitats were dominated by Candidatus Brocadia, Ca. Scalindua and unclassified genes based on the phylogenetic analysis. From river to mangrove, the dominant species of Anammoxers shifted from Ca. Brocadia to Ca. Scalindua with the increase of salinity, and redundancy analysis showed that salinity was an important factor in shaping the community of anammox bacteria. [Conclusion] The community structure of anammox bacteria is different in different habitat, and environmental differences directly affected the population distribution and the evolution of anammox bacteria.