Pseudohongiella nitratireducens sp nov,:, isolated from seawater, and emended description of the genus Pseudohongiella

Two Gram-stain-negative, aerobic, motile by a single polar flagellum and rod-shaped strains, designated SCS-49(T) and SCS-111, were isolated from seawater of the South China Sea. The two strains grew at 4-35 degrees C, with 0.5-7.5% (w/v) NaCl and at pH 6.5-9.0 and were able to reduce nitrate. Q-8 was the sole ubiquinone. The major fatty acids of the two strains were C-16 : 0, C-18 : 1 omega 7c and summed feature 3 (C-16 (:) (1)omega 7c and/or C-16 : 1 omega 6c). The polar lipids included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phospoglycolipid, three unidentified glycolipids, five unidentified phospholipids and two to three unidentified lipids. The isolates formed a stable clade with Pseudohongiella acticola and Pseudohongiella spirulinae based on phylogenetic analysis of 16S rRNA gene sequences. Strains SCS-49(T) and SCS-111 exhibited 16S rRNA gene sequence similarity values of 97.2 and 96.0% with respect to the type strains of P. acticola and P. spirulinae, respectively. The average nucleotide diversity and in silico DNA DNA hybridization values between strain SCS-49(T) and P. acticola KCTC 42131(T) were 71.4 and 25.1%, respectively and the values between strain SCS-49(T) and SCS-111 were 99.9 and 99.2%, respectively. Based upon the phenotypic, chemotaxonomic and genetic data, strains SCS-49(T) and SCS-111 represent a novel species in the genus Pseudohongiella, for which the name Pseudohongiella nitratireducens sp. nov. is proposed. The type strain is SCS-49(T) (=CGMCC 1.15425(T)=KCTC 52155(T)=MCCC 1K03186(T)).