Rhodoligotrophos defluvii sp. nov., isolated from activated sludge.

A Gram-stain-negative, non-spore-forming, non-motile, short-rod-shaped and aerobic bacterial strain (designated lm1T) was isolated from propylene oxide saponification wastewater activated sludge obtained from a wastewater treatment facility in Binzhou (Shandong province, PR China). Strain lm1T grew between 15 and 45 °C (optimum, 40 °C). The pH range for growth was at pH 4.0-10.0 (optimum growth at pH 8.0). The range of NaCl concentration for the growth of strain lm1T was 0-4.0 % (w/v), with optimum growth at 1.0-2.0 % (w/v). Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain lm1T belonged to the genus Rhodoligotrophos and was closely related to Rhodoligotrophos appendicifer JCM 16873T (96.7 % 16S rRNA gene sequence similarity) and Rhodoligotrophosjinshengii CCTCC AB2013083T (96.2 %). The average nucleotide identity value and the digital DNA-DNA hybridization value between strain lm1T and R. appendicifer JCM 16873T were 73.4 and 14.3 %, respectively. The major cellular fatty acids of strain lm1T were C19 : 0cyclo ω8c, C18 : 1ω7c and C16 : 0. Strain lm1T contained Q-10 as the predominant respiratory quinone. The polar lipid profile was composed of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, diphosphatidylglycerol, three unidentified aminolipids, one unidentified glycolipid and five unknown lipids. The G+C content of the genomic DNA was 64.4 mol%. Based on polyphasic taxonomic data, strain lm1T could be classified as a representative of a novel species of the genus Rhodoligotrophos, for which the name Rhodoligotrophosdefluvii sp. nov. is proposed. The type strain is lm1T (=CCTCC AB2019071T=KCTC 72156T).