采用FISH、DGGE和Cloning对短程脱氮系统中硝化菌群的比较分析

针对4种不同的实际污水短程生物脱氮系统(SBR大型中试反应器、UASB-A/O小型反应器、A/O中试反应器和SBR小型反应器),采用Fish、PCR-DGGE和PCR-Cloning-Sequencing分子生物学方法对系统中硝化菌群AOB和NOB进行定性与定量化分析.Fish结果表明,在4种短程脱氮系统中,AOB相比于NOB已成为明显的优势菌群,占总菌群的3%～12%;在SBR中试和小试反应器中没有检测出NOB;A/O中试反应器中存在极少量的Nitrospira(＜0.2%),而UASB-A/O小型反应器中存在极少量的Nitrobacteria(＜0.2%).PCR-DGGE结果表明SBR中试、A/O和UASB-A/O 3种短程脱氮系统中的AOB均以Nitrosomonas-like为主.SBR大型中试反应器中污泥样品的PCR-Cloning-Sequencing结果表明,所有的克隆相似于Nitrosomonas,其中60%以上的克隆相似于Nitrosomonas europaea.

Analysis of nitrifying bacteria in short-cut nitrification-denitrification processes by using FISH, PCR-DGGE and Cloning

Molecular biology techniques of Fish, PCR-DGGE and PCR-Cloning-Sequencing were used to qualitatively and quantitatively analyze ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in SBR large pilot-scale plant, UASB-A/O lab-scale reactor, A/O pilot-scale plant and SBR lab-scale reactor with the performance of short-cut nitrification-denitrification treating actual wastewater. Fish results showed that in the above 4 processes, AOB became dominant with compared to NOB and accounted for 3%~12% of total biomass. No NOB was detected in both SBR pilot-scale and lab-scale reactors. A very small amount of Nitrospira and Nitrobacteria below 0.2% was found in A/O pilot-scale plant and UASB-A/O lab-scale reactor, respectively. PCR-DGGE results showed that the AOB in SBR pilot-scale, A/O pilot-scale and UASB-A/O lab-scale processes were phylogenetically related to Nitrosomonas-like species with a melting point in the range 30% to 50%. PCR-Cloning-Sequencing results showed that all clones from the sludge sample of the SBR large pilot-scale plant were affiliated with Nitrosomonas and 60% of the clones were affiliated with Nitrosomonas europaea.