Comprehensive Analysis of Soil Bacterial Community Structure in King George Island, Maritime Antarctica

Abstract

In recent years, applications of molecular methods to study microbial ecology have allowed the extension of our knowledge that Antarctica contains unexpected high diversity of bacteria and their complex of community. We conduct a comprehensive analysis of bacterial communities in soil samples from Barton Peninsular in Antarctica. Total 263 samples from 51 sites were collected from December of 2010 to February of 2012. Among these samples, we here presented the preliminary results with 85 samples. On the basis of the 16S rRNA genes amplicon using next generation sequencing, total 172,198 sequence reads were obtained and 9,673 OTUs were defined using 97% similarity cutoff. Actinobacteria (21.4%), Proteobacteria (20.0%), Acidobacteria (11.3%) and Chloroflexi (11.1%) were dominant across all habitats. Interestingly, candidate phylum AD3 (4.0%) was abundant in several soil samples, which has not been recognized in previous studies. The bacterial community structures confirmed habitat specific with significant patterns that the predominant phylum is Bacteroidetes in coastal soil, Proteobacteria in upper layer soil and Actinobacteria in lower layer soil. These findings may be inferred that the bacterial specific adaptation to these terrestrial environments was affected by the underlying soil parameters.