Niabella beijingensis sp. nov. and Thermomonas beijingensis sp. nov., two bacteria from constructed wetland

Two Gram-stain-negative, aerobic, non-motile and rod-shaped bacterial strains designated 3A5MI-3(T) and RSS-23(T) were isolated from the Dragon-shaped Wetland System in Beijing Olympic Park, PR China. Strain 3A5MI-3(T) grew at 15–45 °C, pH 5.0–9.0 and with 0–2 % NaCl (w/v), and strain RSS-23(T) grew at 15-40 (o)C, pH 5.5–9.0 and with 0–1 % NaCl (w/v). Phylogenetic analyses of 16S rRNA gene sequences revealed that strains 3A5MI-3(T) and RSS-23(T) were members of Bacteroidetes and Proteobacteria , respectively. Phylogenetically closest relatives of strains 3A5MI-3(T) and RSS-23(T) were Niabella pedocola R384(T) and Thermomonas aquatica SY21(T), respectively. The cells of strain 3A5MI-3(T) contained menaquinone MK-7 and phosphatidylethanolamine, and the major cellular fatty acids were composed of iso-C(15 : 0), iso-C(15 : 1) ω6c and/or iso-C(15 : 1) ω7c, iso-C(17 : 0) 3-OH, C(16 : 0) and summed feature 3 (C(16 : 1) ω7c/C(16 : 1) ω6c). Strain RSS-23(T) contained ubiquinone Q-8 and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unknown phospholipids and an unknown lipid, and its major cellular fatty acids were iso-C(15 : 0), iso-C(17 : 1) ω9c, iso-C(11 : 0) 3-OH and summed feature 3 (C(16 : 1) ω7c/C(16 : 1) ω6c). DNA sequencing resulted in 6.59 Mb for the strain 3A5MI-3(T) genome and 2.79 Mb for the strain RSS-23(T) genome. The calculated G+C molar contents for strains 3A5MI-3(T) and RSS-23(T) were 47.07 and 61.21 mol%, respectively. According to phenotypic and phylogenetic characteristics, strains 3A5MI-3(T) and RSS-23(T) represent novel species of the genera Niabella and Thermomonas for which the names Niabella beijingensis sp. nov. and Thermomonas beijingensis sp. nov. are proposed. The type strain for N. beijingensis sp. nov. is 3A5MI-3(T) (=CGMCC 1.17737(T)=KCTC 82817(T)). The type strain for T. beijingensis sp. nov. is RSS-23(T) (=CGMCC 1.17738(T)=KCTC 82820(T)).