南极长城站空气微生物的分子生态学分析

Abstract

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。

Bacteria are an important component of aerosols,which are closely connected with human life.This study analyzed the community structure of air-borne bacteria at the Great Wall Station,Antarctica,based on 16S rRNA gene clone library analysis.High diversity of airborne bacteria was observed in the aerosol samples.Ninety-three sequences from the clone library could be classified into 53 OTUs(Operation Taxonomic Units) based on 97% sequence 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 sequences accounted for 65.7% of the clone library.Sequences derived from marine and terrestrial environments accounted for 30.1% of the library,suggesting a strong atmospheric exchange between land and sea at the Great Wall Station.In addition,there were 15 sequences related to human activity,indicating that human influence has already affected the airborne microbial community structure at the Great Wall Station.