Parerythrobacter lacustris sp. nov., a novel member of the family Erythrobacteraceae isolated from an inland alpine lake.

A novel bacterium, designated as strain RS5-5, was isolated from lake water in northwestern China. Cells of the isolate were observed to be rod shaped and Gram stain negative. Its growth occurred at 4-37 ℃, pH 6.5-9.0 and in the presence of 0-5% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain RS5-5 was most closely related to Qipengyuania sediminis GDMCC 1.2497 (97.5%), followed by Erythrobacter dokdonensis DSW-74 (97.3%) and Qipengyuania algicida GDMCC 1.2535 (97.0%). Phylogenomic analysis revealed that strain RS5-5 formed a distinct branch with the genus Parerythrobacter. The sole quinone was ubiquinone-10, and the major fatty acids (≥ 10%) were unsaturated fatty acids including C ω6c, summed feature 3 (C ω7c/C ω6c) and summed feature 8 (C ω7c/C ω6c). The polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, one unidentified sphingoglycolipid, three unidentified glycolipids, one unidentified aminoglycolipid, one unidentified aminolipid, two unidentified phospholipids and four unidentified polar lipids. Chemotaxonomic characteristics of strain RS5-5 were coincident with those of the genus Parerythrobacter members. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between strain RS5-5 and two Parerythrobacter reference strains were in the ranges of 73.2-77.7%, 69.0-78.0% and 18.9-20.4%, respectively. The genomic DNA G + C content of strain RS5-5 was 64.1%. The results of phenotypic, phylogenetic and genomic analyses suggested that strain RS5-5 represents a novel species in the genus Parerythrobacter, for which the name Parerythrobacter lacustris sp. nov. is proposed. The type strain is RS5-5 (= GDMCC 1.3163 = KCTC 92277).