Aliifodinibius salipaludis sp. nov., Isolated from Saline-Alkaline Soil

Abstract

A Gram-staining-negative, oblong or rod-shaped, non-flagellated and facultatively anaerobic bacterium, designated WN023^T, was isolated from natural saline-alkali wetland soil of Binhai new district, Tianjin, China. The colonies of strain WN023^T on marine agar 2216 (MA) have a brown, circular, wet pigmentation, and its cells are approximately 1-1.5 μm × 2.0-2.5 μm in size. Growth occurred at 15-45 °C, but optimally at 33-37 °C, in the presence of 5.0-25.0% (w/v) NaCl, but optimally at 10.0-15.0% (w/v) NaCl, and at a pH 6.5-11.0, but optimally at 7.5-8.0. Phylogenetic analysis of the 16S rRNA gene indicates that strain WN023^T is a member of the genus Aliifodinibius within the family Balneolaceae, and the 16S rRNA gene sequence similarity of strain WN023^T with its close relative Aliifodinibius halophilus KCTC 42497^T, Aliifodinibius salicampi KACC 19060^T, Aliifodinibius roseus KCTC 23442^T, Aliifodinibius sediminis ACCC 10714^T, and Fodinibius salinus ACCC 10716^T was 97.3%, 94.5%, 93.9%, 93.71%, and 92.7%, respectively. Strain WN023^T contained menaquinone-7 (MK-7) as the predominant menaquinone, and iso C_15:0, Sum in feature 3 (C_16:1ω6c and/or C_16:1ω7c), and iso C_17:1ω9c as the major fatty acids. The major polar lipids were glycolipid (GL), aminolipid (AL), phospholipid (PL), phosphatidylcholine (PC), phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and lipid (L). The size of the draft genome as presented here was 3,583,276 bp in size, and the G+C content is 42.2 mol%. These combined physiological, biochemical, phylogenetic, and genotypic data supported placement of strain WN023^T in the genus Aliifodinibius and indicated that it was distinct from all other members in the genus Aliifodinibius. This was also confirmed by the low DNA-DNA hybridization values (38.4%) between strain WN023^T and the most closely related recognized Aliifodinibius species-A. halophilus KCTC 42497^T. Therefore, we propose a novel species in the genus Aliifodinibius to accommodate the novel isolate: Aliifodinibius salipaludis sp. nov. (type strain WN023^T = KCTC 52855^T = ACCC 19978^T).

Keywords: Aliifodinibius salipaludis; Balneolaceae; Saline-alkaline soil.