The Polyphasic Taxonomy Of A Marine Bacteria FT102 And Its Genome Sequence Analysis

A taxonomic study employing a polyphasic approach was carried out on strain FT102, which was isolated from a deep-sea sediment sample collected in the south-west Indian Ocean at a depth of 2784 m. The second-generation sequencing platform Illumina was used to sequence the genome.The strain FT102 was Gram-stain-negative, rod-shaped, non-motile and non spore-forming. It grew optimally at 37–42 °C, p H 6.5–8.5 and in the presence of 1–4%(w/v) Na Cl. Phylogenetic analysis of 16 S r RNA gene sequences confirmed the separation of the novel strain from recognized members of the genus Kangiella that are available in public databases. Strain FT102 exhibited 95.5–98.6% 16 S r RNA gene sequence similarity to the type strains of the eight recognized species of the genus Kangiella. The chemotaxonomically characteristic fatty acid iso-C15:0 and ubiquinone Q-8 were also detected. The major polar lipids were DPG, PE, PG and PME. The DNA G+C content of strain FT102 was 45.0%. The mean DNA–DNA relatedness values between strain FT102 and the type strains of Kangiella aquimarina JCM 12318 and Kangiella koreensis JCM 12317 were 47.3 % and 13.7 %, respectively. The combined results of phylogenetic, physiological and chemotaxonomic studies indicated that strain FT102 was affiliated with the genus Kangiella which belongs to the Family Alcanivorax, Order Oceanospirillales and Class Gammaproteobacteria but differed from the recognized species of the genus Kangiella. Therefore, strain FT102 represents a novel species of the genus Kangiella, for which the name Kangiella profundi sp. nov. is proposed. The type strain is FT102T(= CGMCC 1.12959 T = KCTC 42297 T = JCM 30232T)Physical gaps in the genome of FT102 were filled by the PCR reactions. FT102 contained a single circular chromosome of 2,647,333 bp and it ecoded 2,442 different kind of proteins. There was no significant difference of the COG classification in the protein-coding genes of the model strain K. koreensis JCM 12317 and K. geojedonensis KCTC 23420. The good collinearity between the genome of FT102 and K. koreensis JCM 12317 was found. The phylogenetic analysis based on proteins which were ecoded by the five house-keeping genes(rec A, gyr B, atp B, trp B and rpo B) showed that FT102, K. koreensis JCM 12317 and K. aqumarina JCM 12318 had a closest evolutionary distance.A polyphasic taxonomic was carried on the model strain FT102 of Kangiella profundi sp.nov. The whole genomic information of the strain was sequenced. Our study made a good foundation for a further understanding of the physiological and ecological functions of the Kangiella genus which has a unique phylogenetic position.