A non-motile, Gram-stain-positive, rod-shaped bacterium, designated RP-3-7T, was isolated from soil sampled at the Arctic region in Cambridge Bay, NU, Canada. Cells were strictly aerobic, non-spore-forming, catalase-positive and oxidase-positive. Colonies on Reasoner's 2A agar plates were pale yellow-coloured. Strain RP-3-7T was psychrotolerant and grew optimally at 15-20 °C. Strain RP-3-7T assimilated d-glucose, d-mannitol, l-arabinose and l-proline; tolerated only 0.5 % NaCl (w/v). Phylogenetic analysis based on its 16S rRNA gene sequence revealed that strain RP-3-7T formed a lineage within the family Microbacteriaceae and clustered with members of the genus Glaciihabitans. The closest member was Glaciihabitans tibetensis MP203T (98.26 % sequence similarity). The major respiratory quinone was MK-10. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The major cellular fatty acids were anteiso-C15 : 0, iso-C16 : 0, anteiso-C17 : 0 and anteiso-C15 : 1 A. The diagnostic amino acid was 2,4-diaminobutyric acid and whole-cell sugars were xylose, rhamnose and mannose. The DNA G+C content of strain RP-3-7T was 66.9 mol%. The average nucleotide identity and in silico DNA-DNA relatedness values between strain RP-3-7T and Glaciihabitans tibetensis MP203T were 73.79 and 20.1 %, respectively. Based on the polyphasic, genomic and phylogenetic data, strain RP-3-7T represents a novel species of the genus Glaciihabitans, for which the name Glaciihabitans arcticus sp. nov. is proposed. The type strain is RP-3-7T (=KEMB 9005-731T=KACC 21151T=NBRC 113769T).
Keywords: Arctic soil; DAB; Glaciihabitans arcticus sp. nov.; psychrotolerant.