[Effects of 2-chlorophenol-acclimation on microbial community structure in anaerobic granular sludge]

The microbial community structure in 2-chlorophenol-acclimated anaerobic granular sludge and inoculating sludge were analyzed by 16S rDNA-based approach. Total DNA was extracted directly from the inoculating sludge and 2-CP-acclimated anaerobic sludge, and then amplified by polymerase chain reaction (PCR) technique with the specific primer pair ARC21F/ARC958R for Archaea and 31F/907R for Acidobacteria respectively. The positive PCR products were cloned and sequenced. The sequences analysis shows that there exist common Archaea in both sludge, including Methanothrix soehngenii, Methanosaeta concilii and uncultured euryarchaeote etc. Some special Archaea appear in the 2-CP-acclimated sludge, such as Methanobacterium aarhusense, Methanobacterium curvum and Methanobacterium beijingense etc. Others originally existed in the inoculating sludge disappear after acclimation. Common Acidobacteria are found in both sludge, including uncultured bacterium, uncultured Acidobacterium and unknown Actinomycete (MC 9). Some special microbes originally existed in the inoculating sludge, such as Desulfotomaculum sp. 176, uncultured Deltaproteobacterium n8d and uncultured hydrocarbon seep bacterium etc. disappear after acclimation, and uncultured Holophaga/Acidobacterium, uncultured Acidobacteria bacterium and unidentified Acidobacterium are found after 2-CP-acclimation.