sp. nov., a new cold-adapted member of the family Micrococcaceae isolated from Antarctic fellfield soil.

An aerobic, Gram-stain-positive and non-spore-forming strain, designated C1-1, was isolated from a fellfield soil sample collected from frost-sorted polygons on Jane Col, Signy Island, Maritime Antarctic. Cells with a size of 0.65-0.9×1.2-1.7 µm have a flagellar motile apparatus and exhibit a rod-coccus growth cycle. Optimal growth conditions were observed at 15-20 °C, pH 7.0 and NaCl concentration up to 0.5 % (w/v) in the medium. The 16S rRNA gene sequence of C1-1 showed the highest pairwise similarity of 98.77 % to NBRC 113092. Phylogenetic trees based on the 16S rRNA and whole-genome sequences revealed that strain C1-1 belongs to the genus and is most closely related to members of the ' group'. The G+C content of genomic DNA was 58.95 mol%. The original and orthologous average nucleotide identities between strain C1-1 and NBRC 113092 were 77.15 % and 77.38 %, respectively. The digital DNA-DNA relatedness values between strain C1-1 and NBRC 113092 was 21.6 %. The polar lipid profile was composed mainly of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and an unidentified glycolipid. The predominant cellular fatty acids were anteiso-C (75 %) and anteiso-C (15.2 %). Menaquinone MK-9(H) (86.4 %) was the major respiratory quinone in strain C1-1. The peptidoglycan type was determined as A3α (l-Lys-l-Ala; A11.6). Based on all described phylogenetic, physiological and chemotaxonomic characteristics, we propose that strain C1-1 (=DSM 112353=CCM 9148) is the type strain of a novel species sp. nov.