Niabella defluvii sp. nov., isolated from influent water of a wastewater treatment plant

Strain I65 T (=KACC 22647 T =JCM 35315 T ), a novel Gram-stain-negative, strictly aerobic, non-motile, non-spore-forming, rod-shaped, and orange-pigmented bacterium was isolated from influent water of a wastewater treatment system after treatment with several antibiotics, such as meropenem, gentamicin, and macrolide. The newly identified bacterial strain I65 T exhibits significant multi-drug and heavy metal resistance characteristics. Strain I65 T was grown in Reasoner's 2A medium [0 %–2 % (w/v) NaCl (optimum, 0 %), pH 5.0–10.0 (optimum, pH 7.0), and 20–45°C (optimum, 30 °C)]. Phylogenetic analysis based on 16S rRNA gene sequencing confirmed that strain I65 T was closely related to Niabella yanshanensis CCBAU 05354 T (99.56 % sequence similarity), Niabella hibiscisoli THG-DN5.5 T (97.51 %), and Niabella ginsengisoli GR10-1 T (97.09 %). Further analysis of the whole-genome sequence confirmed that the digital DNA–DNA hybridization, average nucleotide identity, and average amino acid identity values between strain I65 T and N. yanshanensis CCBAU 05354 T were 23.4, 80.7, and 85.0 %, respectively, suggesting that strain I65 T is distinct from N. yanshanensis . The genome size of strain I65 T was 6.1 Mbp, as assessed using the Oxford Nanopore platform, and its genomic DNA G+C content was 43.0 mol%. The major fatty acids of strain I65 T were iso-C 15 : 0 and iso-C 15 : 1 G, and the major respiratory quinone was MK-7. Moreover, the major polar lipid of strain I65 T was phosphatidylethanolamine. Based on genotypic, chemotaxonomic, and phenotype data, strain I65 T represents a novel species belonging to the genus Niabella , for which the name Niabella defluvii sp. nov. is proposed. The type strain is I65 T (=KACC 22647 T =JCM 35315 T ).