Hymenobacter polaris sp. nov., a psychrotolerant bacterium isolated from an Arctic station

Abstract

A pink-pigmented, non-motile, Gram-stain-negative, rod-shaped bacterium, designated RP-2-7(T), was obtained from soil sampled at the Arctic station, Spitsbergen, Svalbard, Norway. Cells were strictly aerobic, psychrotolerant, grew optimally at 15-20 degrees Cand hydrolysed CM-cellulose. Phylogenetic analysis based on its 16S rRNA gene sequence revealed that strain RP-2-7(T) formed a lineage within the family Hymenobacteraceae and clustered with members of the genus Hymenobacter. Its closest relative was Hymenobacter marinus KJ035(T) (97.6% sequence similarity). The sequence similarities to other strains were <= 96.9%. The principal respiratory quinone was MK-7 and the major polar lipids were phosphatidylethanolamine and an unidentified aminophospholipid. The predominant cellular fatty acids were summed feature 3 (C-16(:1) omega 7c and/or C-16(:1) omega 6c), anteiso-C-15;0, iso-C-15:0, C-16:1 omega 5c and summed featured 4 (iso-C-17:1 I and/or anteiso-C-17:1 B). The DNA G+C content was 62.8 mol%. In addition, the average nucleotide identity and in silico DNA-DNA hybridization relatedness values between strain RP-2-7(T) and closely related strains were lower than species demarcation thresholds. Based on the resuls of genomic. chemotaxonomic. phenotypic and phylogenetic analyses, strain RP-2-7(T) represents novel species in the genus Hymenobacter, for which the name Hymenobacter polaris sp. nov. is proposed. The type strain is RP-2-7(T) (=KACC 21670(T)=NBRC 114391(T)).