Pseudomonas zhaodongensis sp. nov., Isolated from saline and alkaline soils

Strain NEAU-ST5-21 was isolated from saline and alkaline soils in Zhaodong City, Heilongjiang Province, China. It was aerobic, Gram-stain-negative, rod-shaped and motile with a polar flagellum. It produced yellow–orange colonies with a smooth surface, and grew in the presence of 0–5% (w/v) NaCl (optimum 0%, w/v), at temperatures of 20–40 °C (optimum 28 °C) and at pH 7–11 (optimum pH 7). Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that strain NEAU-ST5-21 belongs to the genus Pseudomonas in the class Gammaproteobacteria. The most closely related species is Pseudomonas xanthomarina, whose type strain (KMM 1447) showed gene sequence similarities of 99.0% for 16S rRNA, 81.8% for gyrB and 85.0% for rpoD with strain NEAU-ST5-21. DNA–DNA hybridization values between strain NEAU-ST5-21 and P. xanthomarina DSM 18231, Pseudomonas kunmingensis CGMCC 1.12273, Pseudomonas stutzeri DSM 5190, Pseudomonas oleovorans subsp. lubricantis DSM 21016, Pseudomomas chengduensis CGMCC 2318, Pseudomonas alcaliphila DSM 17744 and Pseudomonas toyotomiensis DSM 26169 were 52±0% to 25±2%. The DNA G+C content of strain NEAUST5-21 was 65 mol%. The major fatty acids (>10%) were C: ω7c and/or C: ω6c, C: ω7c and/or C: ω6c and C: , the predominant respiratory quinone was ubiquinone 9, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid, phosphatidylglycerol, one unknown aminolipid, one unknown lipid and a glycolipid. The proposed name is Pseudomonas zhaodongensis sp. nov., NEAU-ST5-21 (=ACCC 06362=DSM 27559) being the type strain