Genome Analysis Of Polaromonas Glacialis Strain R3-9, A Bacterium Isolated And Identified From Arctic Glacial

Microbial resources are a great of sorts and different functions. Bacteria is one of the important members of the microbial communities, not only as the primary producer for the ecosystem provides a source of energy, but also plays an important role as decomposers in material recycling and conversion of the ecosystem. Glacial frozen soil is wide-spead in the north and south poles areas. With high biological productivity, glacier is an important part of polar ecosystems. In addition, bacteria is always living in the harsh polar adversity environment, it has a good mechanism to adapt with the extremely low temperature and oligotrophic. Comprehensively studying the composition and characteristics of the genome of the glacier bacteria, is conducive to understanding the strain resilience regulation mechanisms and the key genes to tolerant the extreme environment, as well as lay the foundation for directional filtering and building engineering strains.36 strains which were belonged to 17 genera were isolated and identified from arctic glacial frozen soil, because the R3-9 strain cells are able to grow well at relatively low temperatures, we choose this strain to be deeper genome component and character analysis using whole genome sequencing, which was accommodate Gram-negative, rod-shaped, psychrophilic bacteria. A 16S rRNA gene analysis revealed that strain R3-9 shares high identity with the many strains of Polaromonas genera. The 16S rRNA gene sequence similarity between strain R3-9 and Polaromonas glacialis Cr4-12T phylogenetically closely related neighbor was 98.54%, suggesting that strain R3-9 is a member of the P. glacialis species.The genome of the Polaromonas glacialis Strain R3-9 was sequenced on the Illumina HiSeq2000 platform using a 90-bp paired-end library with an insert size of 500bp and 6000bp. Following the manufacturer’s protocol,142.69 fold coverage data and a total of 754 Mb of filtered paired-end reads were obtained. All reads were assembled into 59 contigs and 27 scaffolds using SOAP denovo version 1.05. Protein-coding sequences were predicted and analyzed using Glimmer 3.0, and functional annotation of genes was performed by BLASTp searching of the KEGG, Clusters of Orthologous Groups (COG), Swiss-Prot, TrEMBL, and NR databases. rRNA and tRNA genes were detected by using RNAmmer and tRNAscan-SE, respectively. Transposons were predicted by RepeatMasker and RepeatProteinMasker, and tandem repeat sequences were analyzed by Tandem Repeats Finder. The information contained in the draft genome comprised 5,284,042 bp of sequence data, with a mean GC contentof 62.27%, and the data cover a total of 5,375 predicted coding sequences (CDSs),37 pseudogenes,0 tRNAs,3 rRNAs,112 minisatellite DNAs,47 microsatellite DNAs, and 4,577 proteins. The number of tandem repeat sequences was 198, and the total length of the tandem repeat sequences was 19,289 bp, which makes up 0.36% of the genome. Among the 4,577 genes identified,4,113 were classified into 34 certain functional KEGG sets. According to the KEGG pathway analysis results, many Polaromonas glacialis Strain R3-9 genes matched to butanoate metabolic pathway, purine metabolism pathway, propanoate metabolism pathway, methane metabolism pathway, naphthalene metabolism pathway, nitrogen metabolism pathway, there are also many genes matching to pyruvate metabolism pathway, oxidative phosphorylation pathway, chlorophyll metabolism pathway, photosynthesis pathway, which indicated that strain R3-9 play an important role of the ecological environment substance transformation and energy conversion.The Polaromonas glacialis Strain R3-9 genome sequence has been deposited at DDBJ/EMBL/GenBank under accession number JMDZ00000000.Knowing the genome sequence of P.glacialis strain R3-9 allows us to begin developing an integrated understanding of the physiology, genetics, ecology, and evolution of this psychrophilic bacterium, also understanding of glacier microbial resources. This study is going to lay the foundation for glacier bacterial functional genomics research.