Microbiome and Microbial Profiling of Arctic Snow Using Whole Genome Sequencing, Psychrophilic Culturing, and Novel Sampling Techniques

Recent advances in massively parallel DNA sequencing have enabled researchers to study new areas of extreme environments. Of particular interest to many researchers are areas of the Arctic that have yet to be comprehensively examined using DNA techniques. These modern approaches to microbial profiling provide new critical data on systems biology not yet seen before from Arctic samples. The discovery of new microbes, microbial biochemical pathways, and biosynthetic gene clusters are critically important when characterizing the Arctic snow microbiome and can provide insights to discovering valuable biosynthetic gene clusters. In this study, 2 L of snow was collected from 15 sites 12 km east outside of Ilulissat, Greenland, using DNA-free sterile techniques. Snow was allowed to melt and immediately concentrated using the InnovaPrep CP sample concentrator. Whole genome DNA sequencing was performed on extracts using both Illumina and Nanopore sequencing as well as psychrophilic culturing. Individual cultures were also sequenced to determine whole genome content and species identity. The results showed a wide-ranging microbiome across the snow fields, including bacteria, yeast, and fungi, with <i>Granulicella, Methylobabcterium, Nostoc, Sphingomonas,</i> and <i>Streptomyces</i> being consistently detected at higher levels across the majority of sites and sequencing platforms, while <i>Belnapia, Chlorogloea, Hymenobacter, Mesorhizobium, Narcardioides, Pseudomonas, Pseudonocardia, Roseomonas,</i> and <i>Solirubrobacter at</i> comparatively lower abundances. The results of culture data for snow sites reveal <i>Pseudomanas</i> sp<i>., Pseudomonas fluorescens Group,</i> unknown Microbacteriaceae sp., <i>Variovorax</i> sp., <i>Robbsia andropogonis,</i> and low concentrations of <i>Aureobasidium sp., Stylodothis sp., Sphingomonas sp., Hymenobacter sp., Caballeronia sordidicola,</i> and two unknown species of yeast and one unknown species of bacteria.