Rowan Arlene K, Snape Jason R, Fearnside David, Barer Michael R, Curtis Thomas P, Head Ian M
Department of Fossil Fuels and Environmental Geochemistry, Centre for Molecular Ecology, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, UK.
FEMS Microbiol Ecol. 2003 Mar 1;43(2):195-206. doi: 10.1111/j.1574-6941.2003.tb01059.x.
Autotrophic ammonia-oxidising bacteria (AOB) are a crucial component of the microbial communities of nitrifying wastewater treatment systems. Nitrification is known to occur in reactors of different configuration, but whether AOB communities are different in reactors of different design is unknown. We compared the diversity and community structure of the betaproteobacterial AOB in two full-scale treatment reactors - a biological aerated filter (BAF) and a trickling filter - receiving the same wastewater. Polymerase chain reaction (PCR) of 16S ribosomal RNA (rRNA) gene fragments with AOB-selective primers was combined with denaturing gradient gel electrophoresis (DGGE) to allow comparative analysis of the dominant AOB populations. The phylogenetic affiliation of the dominant AOB was determined by cloning and sequencing PCR-amplified 16S rRNA gene fragments. DGGE profiles were compared using a probability-based similarity index (Raup and Crick). The use of a probability-based index of similarity allowed us to evaluate if the differences and similarities observed in AOB community structure in different samples were statistically significant or could be accounted for by chance matching of bands in DGGE profiles, which would suggest random colonisation of the reactors by different AOB. The community structure of AOB was different in different sections of each of the reactors and differences were also noted between the reactors. All AOB-like sequences identified, grouped within the genus Nitrosomonas. A greater diversity of AOB was detected in the trickling filters than in the BAF though all samples analysed appeared to be dominated by AOB most closely related to Nitrosococcus mobilis. Numerical analysis of DGGE profiles indicated that the AOB communities in depth profiles from the filter beds were selected in a non-random manner.
自养氨氧化细菌（AOB）是硝化废水处理系统微生物群落的关键组成部分。已知硝化作用发生在不同构型的反应器中，但不同设计的反应器中AOB群落是否不同尚不清楚。我们比较了两个处理相同废水的全尺寸处理反应器——生物曝气滤池（BAF）和滴滤池——中β-变形菌纲AOB的多样性和群落结构。使用AOB选择性引物对16S核糖体RNA（rRNA）基因片段进行聚合酶链反应（PCR），并结合变性梯度凝胶电泳（DGGE），以对优势AOB种群进行比较分析。通过克隆和测序PCR扩增的16S rRNA基因片段，确定优势AOB的系统发育归属。使用基于概率的相似性指数（劳普和克里克）比较DGGE图谱。基于概率的相似性指数的使用使我们能够评估在不同样品中观察到的AOB群落结构的差异和相似性是否具有统计学意义，或者是否可以由DGGE图谱中条带的偶然匹配来解释，这表明不同的AOB对反应器进行随机定殖。每个反应器不同部分的AOB群落结构不同，并且在反应器之间也注意到了差异。所有鉴定出的类AOB序列都归类于亚硝化单胞菌属。尽管所有分析的样品似乎都以与运动亚硝化球菌关系最密切的AOB为主，但在滴滤池中检测到的AOB多样性比BAF中更大。DGGE图谱的数值分析表明，滤床深度剖面中的AOB群落是以非随机方式选择的。
