Exploring diversity of foliose lichen-associated bacterial communities by high throughput ultradeep Illumina sequencing of 16S rRNA hypervariable V3 and V6 region

In the present study used Illumina Sequencing (150*2) of 16S rRNA (V3 and V6 region) to delineate the bacterial communities associated with lichens. The principal coordinate analysis, Venn and bar chart showed obvious microbial changes between the different useful bacteria of lichens belong to Proteobacteria, Acidobacteria, Actinobacteria Gemmatimonadetes, Chloroflexi, Cyanobacteria and several other unclassified groups. Bacterial sequences obtained from five lichen species located on rock outcrops suggested that, each lichen species harbored a variable bacterial community and that all communities were dominated by Alphaproteobacteria. This is the first study in the lichens to delineate the bacterial diversity used the 16S rRNA hypervariable regions V3 and V6. These results confirm the presence of highly diversified bacterial communities existed within lichens and these bacteria may serve distinct functional roles within lichen symbioses.

本研究采用Illumina测序（Illumina Sequencing，150×2）技术，对16S核糖体RNA（16S rRNA）的V3和V6高变区进行扩增测序，以解析与地衣共生的细菌群落结构。本研究通过主坐标分析（Principal Coordinate Analysis）、韦恩图（Venn）与柱状图（bar chart）分析，发现不同地衣样本的细菌群落在组成上存在显著差异，所涉及的菌门包括变形菌门（Proteobacteria）、酸杆菌门（Acidobacteria）、放线菌门（Actinobacteria）、芽单胞菌门（Gemmatimonadetes）、绿弯菌门（Chloroflexi）、蓝细菌门（Cyanobacteria）以及多个未分类类群。本研究从生长于岩石露头处的5种地衣中获取了细菌序列，结果显示每一种地衣均拥有独特的细菌群落结构，且所有群落均以α-变形菌纲（Alphaproteobacteria）为优势类群。本研究是首个采用16S核糖体RNA高变区V3和V6解析地衣细菌多样性的相关研究。本研究结果证实，地衣内部存在高度多样化的细菌群落，且这些细菌在地衣共生体系中可能发挥着各不相同的功能作用。