Crenobacter caeni sp. nov. Isolated from Sludge.

Strain HX-7-9 was isolated from the activated sludge collected from the outlet of the biochemical treatment facility of agricultural chemical plant in Nanjing, Jiangsu province, PR China. Strain HX-7-9 is Gram staining-negative, rod-shaped, non-spore-forming and flagellated. The 16S rRNA gene-based phylogenetic analysis indicate that strain HX-7-9 belongs to the genus Crenobacter, moderately related to Crenobacter luteus YIM-78141 (94.8% similarity). The genomic DNA G+C content of the strain was 67.5 mol%. Strain HX-7-9 was able to grow at 16-45 °C (optimum at 37 °C), at pH 6.0-8.0 (optimum at pH 7.0) and with 0-1% (w/v) NaCl (optimum at 0). Predominant fatty acid constituents were C and summed feature 3 (Cω7c and/or Cω6c). The respiratory ubiquinone was Q-8. The polar lipid profile is composed of diphosphatidylglycerol (DPG), phosphatidylmonomethylethanolamine (PME), phosphatidylethanolamine (PE), phospholipids (PL), glycolipid (GL) and aminophospholipid (APL). The ANI and dDDH values obtained between the genomes of HX-7-9 and C. luteus YIM-78141 were 79.8 and 19.1%, respectively. On the basis of data from phenotypic, chemotaxonomic and genotypic analysis, strain HX-7-9 represents a novel species of the genus Crenobacter, for which the name Crenobacter caeni sp. nov. is proposed. The type strain is HX-7-9 (= KCTC 72654 = CCTCC AB 2019349).