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 G11-30^T 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 G11-30^T formed a lineage in the genus Lacisediminihabitans with the closest phylogenetic Lacisediminihabitans profunda CHu50b-6-2^T and Glaciihabitans tibetensis MP203^T (97.9%, 97.5% 16S rRNA gene sequence similarity). A phylogenomic tree based on genome sequence of G11-30^T, conferred by Type Strain Genome Server (TYGS), separated it from L. profunda CHu50b-6-2^T. Strain G11-30^T 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 G11-30^T and reference strains L. profunda CHu50b-6-2^T and G. tibetensis MP203^T were 20.1 and 20.3%, respectively. Concurrently, Average Nucleotide Identity (ANI) score between strain G11-30 ^T against. profunda CHu50b-6-2^T and G. tibetensis MP203^T 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 G11-30^T (= CCTCC AA 2019080^T = KCTC49359^T).