西双版纳地区热带雨林土壤酸杆菌(Acidobacteria)群体结构和多样性分析

Distribution and Diversity of Acidobacteria in Tropical Rain Forest Soil of Xishuangbanna

摘要:

酸杆菌(Acidobacteria)广泛存在于自然界, 在许多生态系统中发挥重要作用。本文以西双版纳热带森林的土壤为研究对象, 提取土壤的总基因组DNA为模板, 采用特异引物扩增酸杆菌16S rRNA 基因, 构建酸杆菌门细菌16S rRNA 基因克隆文库, 利用限制性片段长度多态性(RFLP)对随机克隆进行筛选、测序, 对该生态环境下酸杆菌菌群种类和组成进行了系统发育分析。结果表明该地区热带森林土壤的酸杆菌有5个类群: 分别为Gp1、Gp2、Gp3、Gp5和1个未知分类的酸杆菌种。其中Gp1是该土壤环境下酸杆菌门的绝对优势菌群, 约占整个酸杆菌群的50%-80%, 其次是Gp2, 占12%-25%, 不同采样点酸杆菌类群的分布趋势是一致的。研究表明西双版纳热带森林土壤中的酸杆菌类群具有适应其土壤环境的广泛的多样性。

Abstract:

Acidobacteria is widely distributed in the nature and plays important roles in various ecosystems. In this study, soil samples were collected from Xishuangbanna Tropical Forest. Community DNA were directly extracted and amplified with the specific primers targeting the 16S rRNA genes of Acidobacteria to construct 16S rRNA gene libraries. The random clones from the libraries were screened and sequenced. Phylogenetic relationship of Acidobacteria in this specific ecosystem was built up. The results showed that members of the identified Acidobacteria belonged to five major groups: Gp1, Gp2, Gp3, Gp5 and an unclassified Acidobacterium. Among them, Gp1 was the most predominant group, about 50%-80%, Gp2 was followed by 12%-25%. Among the samples, the community structure of Acidobacteria was consistent. This study discovered the high diversity of Acidobacteria populations distributed in the soil ecosystems to adapt their specific environments.