PCR-DGGE研究青海农村户用沼气池微生物群落结构

采用变性梯度凝胶电泳(DGGE)分析技术,对青海农村户用沼气池内细菌及古菌群落结构进行分析.结果表明,沼气池含有丰富的细菌及古菌类群,且泥样间的细菌和古菌的群落结构存在差异.4个户用沼气池发酵系统中,细菌分属于5个门,优势类群为拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria).在属分类水平上,属于24个类群,最优势类群为理研菌科佩特里单胞菌属(Petrimonas)、假单胞菌属(Pseudomona)、泰氏菌属(Tissierella)和梭菌属(Clostridium).同时,沼气池发酵系统中古菌主要包括热丝菌属(Thermofilum)、甲烷短杆菌属(Methanobrevibacter)、甲烷囊菌属(Methanoculleus)、产甲烷菌属(Methanogenium),其中,Methanobrevibacter和Methanogenium是沼气池内最优势的产甲烷菌.说明沼气池的产甲烷途径主要是氢营养代谢类型,水解、酸化过程主要由来自动物消化系统内的细菌完成.

Microbial community of rural household biogas digesters in Qinghai by PCR-DGGE

The microbial community composition in rural household biogas digesters of Qinghai was investigated with polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) technology. The results showed that the diversity of bacteria and archaea were rich, and the shift of microbial community was obvious in digesters. The bacterial communities in four biogas digesters were classified into five phyla, Bacteroidetes, Firmicutes and Proteobacteria were identified to be dominant. At genome level, belonging to twenty-four communities, Petrimonas, Pseudomona, Tissierella and Clostridium were the abundant taxa. Meanwhile, the species of archaeal community were calssified as Methanobrevibacter, Methanogenium, Methanoculleus and Thermofilum, and the first two classes were dominant in the digesters. Notably, the methane produced by hydrogen nutrition methanogens, and the dominant fermentative bacteria during the hydrolysis and acidogenesis were detected from animal digestive system.