Lysobacter antarcticus sp. nov., an SUF-system-containing bacterium from Antarctic coastal sediment.

A Gram-stain-negative, heterotrophic, aerobic, non-motile, rod-shaped bacterial strain (GW1-59T) belonging to the genus Lysobacter was isolated from coastal sediment collected from the Chinese Great Wall Station, Antarctica. The strain was identified using a polyphasic taxonomic approach. The strain grew well on Reasoner's 2A media and could grow in the presence of 0-4 % (w/v) NaCl (optimum, 1 %), at pH 9.0-11.0 and at 15-37 °C (optimum, 30 °C). Strain GW1-59T possessed ubiquinone-8 as the sole respiratory quinone. The major phospholipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major fatty acids were summed feature 9 (10-methyl C16 : 0 and/or iso-C17 : 1 ω9c), iso-C15 : 0, iso-C16 : 0, iso-C17 : 0, C16 : 0 and iso-C11 : 0 3-OH. DNA-DNA relatedness with Lysobacter concretionis Ko07T, the nearest phylogenetic relative (98.5 % 16S rRNA gene sequence similarity) was 23.4 % (21.1-25.9 %). The average nucleotide identity value between strain GW1-59T and L. concretionis Ko07T was 80.1 %. The physiological and biochemical results and low level of DNA-DNA relatedness suggested the phenotypic and genotypic differentiation of strain GW1-59T from other Lysobacter species. On the basis of phenotypic, phylogenetic and genotypic data, a novel species, Lysobacter antarcticus sp. nov., is proposed. The type strain is GW1-59T (=CCTCC AB 2019390T=KCTC 72831T).

Kaistella gelatinilytica sp. nov., a flavobacterium isolated from Antarctic soil.

A Gram-stain-negative, aerobic, non-spore-forming, rod-shaped, non-motile, yellow-pigmented bacteria, designated strain G5-32T, belonging to the genus Kaistella was isolated from soil collected in the Antarctic. The strain was identified using a polyphasic taxonomic approach. The strain grew in the presence of 0-5% (w/v) NaCl (optimum, 1%), at pH 6.0-9.0 (optimum, pH 8.0) and at 4-28 °C (optimum, 20 °C). The predominant menaquinone was MK-6 (99.4%). The major fatty acids were anteiso-C15:0 (28.2%), iso-C15:0 (16.4%), summed feature 9 (comprising iso-C17:1 ω9c and/or 10-methyl C16:0; 10.6%) and iso-C16:0 (5.9%). A phylogenetic tree based on 16S rRNA gene sequences showed that strain G5-32T formed a lineage within the genus Kaistella with the closest phylogenetic neighbours Kaistella yonginensis HMD1043T, Kaistella chaponensis DSM 23145T, Kaistella jeonii DSM 17048T and Kaistella carnis NCTC 13525T (97.9, 97.8, 97.8 and 98.0 % 16S rRNA gene sequence similarity, respectively). The ANI values between strain G5-32T and K. jeonii DSM 17048T, K. chaponensis DSM 23145T, K. carnis NCTC 13525T and K. yonginensis HMD1043T were 90.9, 82.6, 77.1 and 76.3%. Concurrently, digital DNA-DNA hybridization values of strain G5-32T assessed against K. jeonii DSM 17048T, K. chaponensis DSM 23145T, K. carnis NCTC 13525T and K. yonginensis HMD1043T were 42.3, 25.9, 21.7 and 21.3%, respectively. Based on phenotypic, phylogenetic and genotypic data, a novel species, Kaistella gelatinilytica sp. nov., is proposed. The type strain is G5-32T (=CCTCC AA 2019083T=KCTC 72766T).