Bacterial diversity and chemical pollutants invertigation in ice core of Campbel Glacier in Northern Victora Land in Antarctica

Introduction This study was performed on ice cores drilled in two areas of the Campbell Glacier, a glacier that ends with floating ice tongue of about 130 km of length, located in Northern Victoria Land in Antarctica. The microbiome of glacier biosphere is a reservoir of still undiscovered bacteria and Antarctic glaciers may be a relevant reservoir of microbial biodiversity. Objectives Goals of study were: 1. Detection and identification of living bacteria still present in ice core. 2. Microbiome identification by amplification of 16S rRNA regions coupled to Illumina high-throughput sequencing technology (HTS). 3. Investigation of presence of chemical pollutants polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs) Materials and methods Ice cores were drilled in two areas: Camp4 (74° 13’ 34”S, 163° 58’ 58”E, 8,94 m of depth) and Camp11 (73° 43’ 45”S, 163° 18’ 31”E, 12,30 m of depth). The ice cores were sealed in plastic bags and preserved at -20°C prior to analyses. The ice cores were handled under aseptic conditions and the water obtained from melted ice was used to recover the microbial cell by filtration on membrane, while the water used for chemical analyses. The cells were cultured on R2A agar medium and colonies growth after 10 days of incubation at 4 and 20°C were used for DNA extraction and 16S rRNA analysis. The DNA for HTS analyses of 16S amplicons was extracted from microbial cells recovered on filter membrane by filtration of melted ice core. Results A total ice core samples were melted for microbial and chemical analysis. In fifteen samples was possible recover living bacteria and were identify by 16S rRNA sequencing analysis. The cultured and identified species belong to genera Bacillus, Microbcaterium, Sphingomonas, Paenibacillus, Kocuria.