豆腐废水UASB反应器中的原核生物多样性及主要功能菌群

Phylogenetic Diversity of Prokaryotes and The Main Functional Groups in A UASB Reactor Treating Bean Curd-farm Wastewater

通过构建 16SrRNA基因文库 ,对豆腐废水UASB反应器中颗粒污泥的原核生物多样性进行了分析 ,并用MPN法对颗粒污泥中的互养产乙酸细菌和产甲烷菌进行了活菌数量测定。结果表明 ,33%的 16SrRNA基因序列属于产甲烷菌 ,氢和乙酸盐营养型的产甲烷菌在颗粒污泥中数量最多 ,分别为 1 1× 10 9个 mL和 4 5× 10 8个 mL。低GC革兰氏阳性菌和δ 变形菌纲分支的细菌也是颗粒污泥中的主要菌群 ,它们的 16SrRNA序列分别占 2 2 %和 9% ,其中互养产乙酸细菌在颗粒污泥中的数量可达 4 5× 10 7个 ml。绿色非硫细菌是另一类丰度很高的细菌 ,其 16SrRNA序列占文库的 12 %。对各类微生物在颗粒污泥中可能的作用进行了讨论。通过研究不仅了解了特定环境中的微生物组成 ,还为从中分离特异类群的微生物提供了指导。

Phylogenetic diversity of microorganisms in the UASB granular sludge treating bean curd-farm wastewater was surveyed based on the homology analysis of 16S rRNA sequences obtained from the granules. Quantification of syntrophic acetogenic bacteria and methanogens for degradation of fatty acid in the granules was determined with MPN method. The results indicated that methanogens both of H 2-and acetate-trophors were the most abundant metabolic groups in the granules. 33% of 16S rRNA sequences retrieved from the granules were affiliated to methanogens, and 1.1×10 9 cells/mL and 4.5 ×10 8 cells/mL were counted for H 2-and acetate-trophic methanogens, respectively. Low GC Gram-positive bacteria and Delta-proteobacteria, the two phylogenetic phyla to which syntrophic acetogenic bacteria were affiliated, could also be predominant in the granules, and their 16S rRNA sequences accounted for 22% and 9% respectively, at the same time, their count was determined as high as 4.5×10 7 cells/mL. Green non-sulfur bacteria were another group existing abundantly, 12% of 16S rRNA sequences of them were obtained. Hence phylogentic analysis of an ecosystem could provide a preview for the organism composition before attempting to purify some cultures.