Lacisediminihabitans changchengi sp. nov., an actinobacterium isolated from Antarctic swamplands mud.

A Gram-staining-positive, heterotrophic, non-spore-forming, non-motile, short rod-shaped, strain G11-30T belonging to the genus Lacisediminihabitans was isolated from a swampland mud in Antarctica. The strain was identified using a polyphasic taxonomic approach. The strain grew well on R2A agar media and formed no aerial mycelia and no diffusible pigments on any media tested. The chemotaxonomic results showed 2, 4-diaminobutyric acid (DAB) is the diagnostic diamino acid of the peptidoglycan. MK-10 was the predominant respiratory menaquinone. The major phospholipids were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), unidentified lipid (L) and unidentified glycolipid (GL). The major fatty acids were anteiso-C15:0 (64.5%) and iso-C15:0 (18.7%). A phylogenetic tree based on 16S rRNA gene sequences showed that strain G11-30T formed a lineage in the genus Lacisediminihabitans with the closest phylogenetic Lacisediminihabitans profunda CHu50b-6-2T and Glaciihabitans tibetensis MP203T (97.9%, 97.5% 16S rRNA gene sequence similarity). A phylogenomic tree based on genome sequence of G11-30T, conferred by Type Strain Genome Server (TYGS), separated it from L. profunda CHu50b-6-2T. Strain G11-30T has a complete genome size of 2.59 Mb, with a G + C content of 66.2 mol%. The digital DNA-DNA hybridization (dDDH) score between strain G11-30T and reference strains L. profunda CHu50b-6-2T and G. tibetensis MP203T were 20.1 and 20.3%, respectively. Concurrently, Average Nucleotide Identity (ANI) score between strain G11-30 T against. profunda CHu50b-6-2T and G. tibetensis MP203T were 76.2 and72.5%, respectively. Based on phenotypic, phylogenetic and genotypic data, a novel species, Lacisediminihabitans changchengi sp. nov. is proposed. The type strain is G11-30T (= CCTCC AA 2019080T = KCTC49359T).

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).