Parvibaculum sedimenti sp. nov., A Novel Soil Bacterium Isolated from Sediment.

A Gram-stain-negative, aerobic bacterium, designated HXT-9, was isolated from a river sediment. Cells were rod-shaped and non-motile. Growth occurred at 10-42 ℃ (optimum 30 ℃), at pH 5.0-8.0 (optimum pH 7.0) and with NaCl concentrations of 0-2.5% (optimum 0.5%). Phylogenetic trees based on 16S rRNA gene sequences showed that strain HXT-9 belonged to the genus Parvibaculum, and showed highest similarities to P. lavamentivorans KCTC 22775 (96.1%), followed by P. hydrocarboniclasticum EPR 92 (94.8%) and P. indicum P31 (93.6%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain HXT-9 and P. lavamentivorans KCTC 22775 were 75.2% and 20.8%, respectively. The G + C content of strain HXT-9 genome was 62.1 mol%. The major fatty acids (> 10%) were summed feature 8 (Cω7c and/or Cω6c), C cyclo ω8c and C 3-OH. The major respiratory quinone was ubiquinone 11 (Q-11). The major polar lipids were DPG (diphosphatidylglycerol), PG (phosphatidylglycerol), PME (phosphatidylmonomethylethanolamine), PE (phosphatidylethanolamine), PC (phosphatidylcholine) and AL (unidentified aminolipids). The phylogenetic analysis and physiological and biochemical data showed that strain HXT-9 represents a novel species in the genus Parvibaculum, for which the name P. sedimenti sp. nov. is proposed. The type strain is HXT-9 (= CCTCC AB 2019273 = KCTC 72547).