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

Strain I65T (=KACC 22647T=JCM 35315T), 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 I65T exhibits significant multi-drug and heavy metal resistance characteristics. Strain I65T 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 I65T was closely related to Niabella yanshanensis CCBAU 05354T (99.56 % sequence similarity), Niabella hibiscisoli THG-DN5.5T (97.51 %), and Niabella ginsengisoli GR10-1T (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 I65T and N. yanshanensis CCBAU 05354T were 23.4, 80.7, and 85.0 %, respectively, suggesting that strain I65T is distinct from N. yanshanensis. The genome size of strain I65T 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 I65T were iso-C15 : 0 and iso-C15 : 1 G, and the major respiratory quinone was MK-7. Moreover, the major polar lipid of strain I65T was phosphatidylethanolamine. Based on genotypic, chemotaxonomic, and phenotype data, strain I65T represents a novel species belonging to the genus Niabella, for which the name Niabella defluvii sp. nov. is proposed. The type strain is I65T (=KACC 22647T=JCM 35315T).

Lacibacter luteus sp. nov., isolated from a freshwater river.

An isolate, designated TTM-7T, recovered from a freshwater river in Taiwan, was characterized using a polyphasic taxonomy approach. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain TTM-7T is affiliated with species in the genus Lacibacter. Strain TTM-7T was most closely related to Lacibacter cauensis NJ-8T with a 98.2 % 16S rRNA gene sequence similarity, followed by Lacibacter daechungensis H32-4T (97.4 %) and Lacibacter nakdongensis SS2-56T (96.3 %). Cells were Gram-stain-negative, aerobic, motile by gliding, rod-shaped and formed orange colonies. Optimal growth occurred at 25 °C, pH 7 and 0 % NaCl. The major fatty acids of strain TTM-7T were iso-C15 : 0, summed feature 3 (comprising C16 : 1ω7c/C16 : 1ω6c and/or iso-C15 : 0 2-OH) and iso-C15 : 1 G. The predominant hydroxy fatty acid was iso-C17 : 0 3-OH. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, two unidentified aminoglycolipids, five unidentified aminophospholipids and one unidentified lipid. The major isoprenoid quinone was MK-7. Genomic DNA G+C content of strain TTM-7T was 40.6 mol%. Strain TTM-7T showed 83.6 % average nucleotide identity and 16.0 % digital DNA-DNA hybridization identity with Lacibacter cauensis NJ-8T. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain TTM-7T should be classified in a novel species of the genus Lacibacter, for which the name Lacibacter luteus sp. nov. is proposed. The type strain is TTM-7T (=BCRC 81159T=LMG 30926T=KCTC 62870T).

Filimonas effusa sp. nov., isolated from a freshwater river.

Strain TTM-71T, isolated from a freshwater river in Taiwan, was characterized using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain TTM-71T is affiliated with species in the genus Filimonas. The 16S rRNA gene sequence similarity indicated that strain TTM-71T is closely related to species within the genus Filimonas (94.7-95.5 % sequence similarity) and had a high sequence similarity with Filimonas endophytica SR 2-06T (95.5 %). Strain TTM-71T showed 70.3 % average nucleotide identity and 24.9 % digital DNA-DNA hybridization identity with Filimonas lacunae YT21T. Cells were Gram-stain-negative, aerobic, motile by gliding, rod-shaped and formed beige-colored colonies. Optimal growth occurred at 20 °C, pH 8, and in the presence of 0.5 % NaCl. The major fatty acids of strain TTM-71T were iso-C15 : 0, iso-C15 : 1 G and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c). The predominant hydroxy fatty acid was iso-C17 : 0 3-OH. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, four uncharacterized aminophospholipids, one uncharacterized aminolipid, one uncharacterized phospholipid and one uncharacterized lipid. The predominant polyamine was homospermidine. The only isoprenoid quinone was MK-7. Genomic DNA G+C content was 45.6 mol%. On the basis of the polyphasic evidence presented, strain TTM-71T is considered to represent a novel species of the genus Filimonas, for which the name Filimonas effusa sp. nov. is proposed. The type strain is TTM-71T (=BCRC 81160T=LMG 31017T=KCTC 62871T).