云南热带户用沼气池的原核生物群落结构研究

Prokaryotic community structure of household biogas digesters in the tropical climate zones of Yunnan

摘要:

【目的】揭示云南热带农村户用沼气池中的原核生物(细菌和古菌)的群落结构特征。【方法】采用16S rRNA基因克隆文库技术对云南(北)热带代表性气候区的户用沼气池中的原核生物(细菌和古菌)多样性进行研究。【结果】得到细菌330条有效序列，划分为108个OTUs，文库覆盖度为81.5%；古菌有效序列185条，划分为17个OTUs，文库覆盖度为97.8%。通过GenBank数据库进行相似性比对与系统发育分析，结果表明：大部分细菌为未知细菌(Unclassified bacteria，占24.19%)，优势细菌类群归属拟杆菌门(Bacteroidetes，占23.58%)、绿弯菌门(Chloroflexi，占21.46%)、厚壁菌门(Firmicutes，占13.91%)和变形菌门(Proteobacteria，占8.74%)；古菌主要的优势类群为乙酸盐营养型的甲烷八叠球菌目(Methanosarcinales)的鬃毛甲烷菌属(Methanosaeta，占76.75%)；此外还检测到少量未培养的泉古菌门细菌(Crenarchaeota，占9.19%)。【结论】云南(北)热带代表性气候区的农村户用沼气池中的微生物种类十分丰富，不同微生物种类的丰度存在明显差异，并存在明显优势种群，且细菌比古菌具有更丰富的多样性。

Abstract:

[Objective] Unveil the characteristics of prokaryotic (bacteria and archaea) community structure of household biogas digesters in the tropical climate zones of Yunnan. [Methods] 16S rRNA gene clone library technique was constructed to study prokaryotic (bacteria and archaea) diversity of the household biogas digesters in Yunnan (north) typical tropical climate zones. [Results] Total 330 effective sequences of bacteria were obtained and divided into 108 OTUs, bacterial library coverage is 81.5%; 185 archaeal effective sequences were obtained and divided into 17 OTUs, archaeal library coverage is 97.8%. A typical sequence in each OTUs was selected and to perform similarity comparison and analysis in the GenBank database, the results showed that: most bacteria are uncultured bacteria (24.19%), the dominant bacterial phyla include Bacteroidetes (23.58%), Chloroflexi (21.46%), Firmicutes (13.91%) and Proteobacteria (8.74%); the dominant archaeal group is Methanosaeta (76.75%) of the order Methanosarcinales which is aceticlastic. In addition, a small amount of uncultured Crenarchaeota archaea (9.19%) was detected. [Conclusion] The results showed that microbial species are very rich in the household biogas digesters of Yunnan (north) typical tropical climate zones, different microbial species have obvious differences in the abundance and have obvious dominant population, and the diversity of bacteria is more abundant than that of archaea.