Roseococcus pinisoli sp. nov., lacking pufL and pufM bacteriochlorophyll a: synthesizing genes

A Gram-stain-negative, cocci-to-oval-shaped bacterial strain, designated XZZS9^T, was isolated from the rhizosphere soil of Pinus sylvestris var. mongolica and characterized taxonomically using a polyphasic approach. Growth occurred at 20-35 °C (optimum, 28 °C), pH 6.0-11.0 (optimum, pH 7.0), and in 0-1% NaCl (optimum, 0%). Phylogenetic analysis based on 16S rRNA gene sequencing indicated that strain XZZS9^T was related to members of the genus Roseococcus, with the highest sequence identity to Roseococcus microcysteis NIBR12^T (96.9%). The major cellular fatty acids (> 5% of the total) were C_18:1 ω7c and C_19:0 cyclo ω8c. The major isoprenoid quinone was Q-9 and the polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified glycophospholipid, and an unidentified phospholipid. Genome sequencing revealed that had a genome size of 4.79 Mbp with a G + C content of 69.5%. Comparative genomic analyses clearly separated strain XZZS9^T from the known species of the genus Roseococcus based on average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values below the thresholds for species delineation. Genome annotations did not find pufL and pufM genes in strain XZZS9^T, suggesting a possible lack of photosynthetic reaction. Based on genotypic and phenotypic characteristics, strain XZZS9^T represents a novel species of the genus Roseococcus, for which we propose the name Roseococcus pinisoli sp. nov. The type strain is XZZS9^T (= KCTC 82435^T = JCM 34402^T = GDMCC 1.2158^T).