为了处理晚期垃圾渗滤液,利用膜生物反应器(membrane bioreactor,MBR)实现了稳定亚硝化.分别构建总细菌通用克隆文库和针对亚硝化功能菌氨氧化菌(ammonia oxidizing bacteria,AOB)的功能基因——amoA基因的克隆文库,来研究稳定期亚硝化系统中微生物多样性.从16S rDNA克隆文库中随机挑选82个阳性克隆子进行序列测定,将测序结果与Genbank中已有模式菌株的序列进行比对后发现,亚硝化系统中主要有4个优势菌群,分别是Proteobacteria类群(64.65%)、未培养菌(uncultured bacterium)类群(18.3%)、Bacteroidetes类群(9.76%)、Firmicutes类群(7.32%).构建针对AOB的amoA功能基因的克隆文库,从文库中挑选73个阳性克隆子进行序列测定,经序列比对后发现在系统中仅检测到了亚硝化单胞菌属(Nitrosomonas)和未培养菌,分别占41.1%和58.9%.这表明系统中起到亚硝化作用的微生物种群主要是亚硝化单胞菌属(Nitrosomonas).此外,未培养细菌的大量存在表明,系统中还存在着丰富的微生物资源等待进一步的开发利用.%In order to find the better method to deal with late landfill leachate, the stable partial nitrification system was operated in the MBR ( membrane bioreactor) . The microbial community structure of the stable partial nitrification phase was investigated by the total bacterial clone library and the cloning library of ammonia oxidizing bacteria ( AOB ) functional gene amoA. 82 positive clones were selected randomly from 16S rDNA clone library and their sequence was determined. The results show that there are four dominant bacterium groups in the stable partial nitrification phase: Proteobacteria ( 64. 65%) , uncultured bacterium (18. 3%), Bacteroidetes (9. 76%) , and Firmicutes (7. 32%). Building on the cloning library of AOB' s functional gene amoA, 73 positive clones were selected from the library and their sequence was also determined. Compared with basic local alignment search tool ( BLAST ) , the results show that only the Nitrosomonas and Uncultured bacterium are detected in the system, and their proportion is 41. 1% and 58. 9%, respectively. This phenomenon show that the number of Nitrosomonas is maximum in this system. At the same time, the existence of many unknown bacterial species showed that there are a large number of microbial resources in the system and needing further development.
展开▼