利用PCR-DGGE研究膜生物反应器中微生物的群落结构

使用聚合酶链式反应-变性梯度凝胶电泳技术(PCR-DGGE)考查了天津某再生水处理厂膜生物反应器(Membrane Bioreactor,简称MBR)培养驯化直至正常运行全过程中总细菌群落结构的演替情况.结果表明,在MBR环境中,接种的传统活性污泥中的微生物群落在几天内发生了较大的变化,在进污水驯化时,微生物群落也遭受了冲击,最后经过培养驯化趋于稳定,一些菌种逐渐成长为顶级优势微生物,在反应器内占据主导地位.最终该反应器逐渐形成了自己独有的微生物群落生态系统.另外,对该微生物群落的部分优势总细菌进行了克隆测序和系统发育树分析,通过鉴定获得的10条总细菌的16S rDNA序列,它们分别与气单胞菌属、假单胞菌、亚硝酸菌属、丛毛单胞菌属和杆菌的同源性在97%以上,这些优势微生物在MBR反应器去除有机物的过程中起到了关键的作用.

Microbial community structure in a membrane bioreactor determined using PCR-DGGE

The microbial community structure of an MBR (membrane bioreactor) in a reclaimed water treatment plant of Tianjin was investigated using PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Investigations on the succession of the total bacterial community in the cultivation and domestication process showed that the microbial community of the inoculated traditional activated sludge changed greatly after a few days in the MBR system. The wastewater inflow had a significant impact on the microbial community during the domestication process. However, it finally stabilized as certain bacteria gradually became the dominant species in the reactor. And a unique microbial community ecosystem was gradually formed in the reactor. Part of the microbial community of dominant bacteria was analyzed through cloning, sequencing and phylogenetic analysis. Ten bacterial 16S rDNA sequences were identified. The homology of these bacteria was more than 97% compared with Aeromonas, Pseudomonas, Nitrosomas, Comamonas and Bacillus. These dominant microorganisms played key roles in the removal of organic pollutants in the MBR system.