南极长城站空气微生物的分子生态学分析

摘要

Bacteria are an important component of aerosols,which are closely connected with human life.This study ana-lyzed the community structure of air-borne bacteria at the Great Wall Station,Antarctica,based on 1 6S rRNA gene clone library analysis.High diversity of airborne bacteria was observed in the aerosol samples.Ninety-three se-quences from the clone library could be classified into 53 OTUs (Operation Taxonomic Units)based on 97% se-quence similarity.The Shannon and Simpson index of the clone library were 3.58 and 0.04,respectively.Based on phylogenetic analysis the sequences were affiliated with seven phyla,including Actinobacteria,Cyanobacteria/Chloroplast,Bacteroidetes,Firmicutes,Planctomycetes,Proteobacteria and Verrucomicrobia.Proteobacterial se-quences accounted for 65 .7%of the clone library.Sequences derived from marine and terrestrial environments ac-counted for 30.1%of the library,suggesting a strong atmospheric exchange between land and sea at the Great Wall Station.In addition,there were 1 5 sequences related to human activity,indicating that human influence has al-ready affected the airborne microbial community structure at the Great Wall Station.%微生物是气溶胶的重要组成部分。本研究通过收集南极长城站附近气溶胶，构建气溶胶中空气微生物16S rRNA基因文库，发现南极空气微生物具有很高的多样性，93个克隆子包含了53个OTU（Operational Taxonomic Unit）， Shannon指数为3．58，Simpson指数为0．04。南极长城站空气微生物的主要细菌类群为Actinobacteria、Cyanobacteria/Chloroplasts、Bacteroidetes、Firmicutes、Planctomycetes、Proteobacteria及Verrucomicrobia等7个门，Proteobacteria门的细菌是优势类群，占长城站空气微生物细菌克隆文库的65．7％。克隆文库中海源微生物序列及陆源微生物序列各占30．1％，说明长城站附近具有较强的海陆大气交换。我们发现有15个克隆子序列与人类活动相关，占总克隆子数的16．1％，说明人类活动已经影响到了长城站的空气微生物群落结构。