Bacterial community structure in the surface waters of King George Island (South Shetland Islands, Antarctica). marine metagenome

Planktonic bacteria play key role in biogeochemical cycles and energy flow in marine ecosystems. However, our knowledge of the extent and character of bacterial diversity in polar marine environments is still limited. Here we present the use of high throughput DNA pyrosequencing and statistical inference to assess the diversity of planktonic bacteria in the Maxwell Bay, King George Island, Antarctica. The V4 region of the 16S rRNA gene was amplified from the surface seawater samples. The number of bacterial 16S rRNA sequences obtained from each sites varied from 5289 (G3 site) to 13574 (G5 site). The most abundant bacterial groups in the investigated areas were the Bacteroidetes, Cyanobacteria/chloroplasts, and Proteobacteria. Alpha- and Gamma-proteobacteria accounted for 78%-99% of the Proteobacteria-related sequences. More Beta-proteobacteria was detected in the sites affected by freshwater input.