Planococcus circulans sp. nov., A Novel Bacterium Isolated from Kubuqi Desert Soil

A novel bacterial strain, designated as 4-30^T, was isolated from a soil sample collected from the Kubuqi Desert in Inner Mongolia, northern China. The isolate was a Gram-stain-positive, aerobic, motile, and coccus-shaped bacterium, and its colonies were circular, opaque, convex, smooth, and orange-pigmented on Luria-Bertani agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 4-30^T belonged to the genus Planococcus. Growth occurred at 4-38 °C (optimum, 25-28 °C), pH 6.0-11.0 (optimum, pH 9.0), and in 0-10% (w/v) NaCl (optimum, 1%). Strain 4-30^T contained iso-C_14:0, anteiso-C_15:0, C_16:1ω7c alcohol, and iso-C_16:0 as major cellular fatty acids (>10%) and MK-7 and MK-8 as predominant menaquinones. Its polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and two unidentified polar lipids. The genomic DNA G+C content was 45.9%. The average nucleotide identity (ANI) values between strain 4-30^T and the closely related species were relatively low (ANIm < 85.6%, ANIb < 82.9% and OrthoANIu < 83.3%), and the digital DNA-DNA hybridization (dDDH) between strain 4-30^T and type strains of the genus Planococcus were 20.0-26.7%. Based on phylogenetic, genotypic, chemotaxonomic, and phenotypic analyses, strain 4-30^T is considered to represent a novel species of the genus Planococcus, for which the name Planococcus circulans sp. nov. is proposed. The type strain is 4-30^T (=CDMCC 1.2409^T = KCTC 43405^T).