A beige-pigmented, Gram-stain-negative, aerobic, non-motile, rod-shaped bacterium, named 24T, was isolated from sludge of a pesticide manufacturing factory in Nantong, Jiangsu Province, China. 16S rRNA gene sequence analysis revealed that strain 24T shared highest similarity with Parapusillimonas granuli Ch07T (98.20 %), followed by Candidimonas nitroreducens SC-089T (98.07 %) and Paracandidimonas soli IMT-305T (98.03 %). Phylogenetic trees showed that strain 24T formed a distinct clade with Paracandidimonas soli IMT-305T. The results of DNA-DNA hybridization tests showed that reassociation values were less than 45 % with respect to these closely related type strains. Strain 24T contained Q-8 and putrescine as the major respiratory quinone and polyamine, respectively. The main cellular fatty acids were summed feature 3 (C16 : 1ω7c/C16 : 1ω6c), summed feature 2 (iso-C16 : 1 I/C14 0 3-OH/C12 : 0 aldehyde), summed feature 8 (C18 : 1ω7c/C18 : 1ω6c) and C12 : 0. The polar lipid profile included phosphatidylmethylethanolamin, phosphatidylethanolamine, phosphatidylglycerol, one unidentified phospholipid and one unidentified aminolipid. The G+C content was 56.83 mol%. Combined data from phenotypic, phylogenetic and DNA-DNA relatedness studies demonstrated that strain 24T represents a novel species of the genus Paracandidimonas, for which the name Paracandidimonas caeni sp. nov. is proposed. The type strain is 24T (=CCTCC AB 2018057T=KACC 19692T).
Keywords: Paracandidimonas caeni; taxonomy.