Hymenobacter caeli sp. nov., an airborne bacterium isolated from King George Island, Antarctica

A rod-shaped and Gram-stain-negative bacterial strain 9A(T), was isolated from an air sample collected at King George Island, maritime Antarctica. Phylogenetic analysis based on 16S rRNA gene sequence reveals that strain 9A(T) belongs to the genus Hymenobacter and shows the highest similarity to Hymenobacter coccineus CCM 8649(T) (96.8 %). The DNA G+C content based on the draft genome sequence is 64.9 mol%. Strain 9AT is strictly aerobic, psychrophilic, catalase-positive, oxidase-positive and non-motile. Growth is observed at 0-20 degrees C (optimum 10 degrees C), pH 6.0-8.0 (optimum pH 7.0), and in the absence of NaCl. The predominant menaquinone of strain 9A(T) is MK-7 and the major fatty acids comprise Summed Feature 3 (C-16:1 omega 7c and/or C-16:1 omega 6c; 25.2 %), iso-C-15:0 (23.2 %), C-16:1 omega 5c (11.6 %), Summed Feature 4 (anteiso-C-17:1 B/iso-C-17:1 I) (9.6 %) and anteiso-C-15:0 (9.6 %). The polar lipid profile consists of the major lipid phosphatidylethanolamine and moderate to minor amounts of phosphatidylserine, unidentified aminolipids, aminophospholipids, aminophosphoglycolipids, polar lipids lacking a functional group and an unidentified phospholipid and a glycolipid. In the polyamine pattern sym- homospermidine is predominant. On the basis of the results obtained, strain 9A(T) is proposed as a novel species of the genus Hymenobacter, for which the name Hymenobacter caeli sp. nov. is suggested. The type strain is 9A(T) (=CCM 8971(T)=LMG 32109(T)=DSM 111653(T)).