Antarcticimonas flava gen. nov., sp. nov., isolated from Antarctic coastal seawater.

A marine bacterium, designated IMCC3175(T), was isolated from a seawater sample collected off the Antarctic coast. The strain was Gram-negative, obligately aerobic, carotenoid pigment-containing, and rod-shaped bacterium that divided by binary fission. As determined by 16S rRNA gene sequence comparisons, the most closely related genera were Formosa (92.9 approximately 93.3%), Bizionia (91.6 approximately 93.2%), Gaetbulibacter (91.5 approximately 92.8%), Sediminibacter (92.7%), Yeosuana (92.6%), Subsaximicrobium (92.1 approximately 92.2%), and Gillisia (89.5 approximately 92.2%). Phylogenese analysis based on 16S rRNA gene sequences showed that the strain formed a monophyletic clade together with the genera Sediminibacter and Subsaximicrobium but represented an independent phyletic line in this clade of the family Flavobacteriaceae. The DNA G+C content of the strain was 37.3 mol%. The major respiratory quinone was MK-6 and the predominant cellular fatty acids were C(16:1) omega7c and/or iso-C(15:0) 2-OH (12.8%), anteiso-C(15:0) (9.4%), and iso-C(16:1) (9.4%). Low 16S rRNA gene sequence similarity, formation of a distinct phylogenetic branch, and several phenotypic characteristics, including a narrow range of temperature and salinity for growth, differentiated strain IMCC3175(T) from other related genera in the family Flavobacteriaceae. Therefore the name Antarcticimonas flava gen. nov., sp. nov. is proposed, with strain IMCC3175(T) (=KCCM 42713(T) =NBRC 103398(T)) as the type strain.