Domibacillus tundrae sp. nov., isolated from active layer soil of tussock tundra in Alaska, and emended description of the genus Domibacillus

Abstract

A novel Gram-positive, spore-forming, aerobic, motile and rod-shaped bacterium designated as strain PAMC 80007T was isolated from active layer soil sample of Council, Alaska. Optimal growth of strain PAMC 80007T was observed at 30 ºC, pH 7.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain PAMC 80007T belonged to the genus Domibacillus. This strain was closely related to Domibacillus enclensis (98.3 %), Domibacillus robiginosus (98.3 %) and Domibacillus indicus (97.2 %). Genomic DNA G+C content was 43.5 mol % and genomic relatedness analyses based on the average nucleotide identity and the genome-to-genome distance showed that strain PAMC 80007T is clearly distinguished from the closely related Domibacillus species. The major fatty acids (>5 %) were iso-C15:0 (24.7 %), C16:1 ω11c (16.8 %), anteiso-C15:0 (16.5 %), C16:0 (15.6 %) and anteiso-C17:0 (8.7 %). The major respiratory isoprenoid quinones were menaquinone-6 (MK-6) and menaquinone-7 (MK-7), and the polar lipid profile contained diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphoglycolipid (PGL), phospholipid (PL) and two unidentified lipids (L1, L2). meso-diaminopimelic acid (type A1γ) was present in the cell-wall peptidoglycan and the major whole-cell sugar was ribose and minor quantity of glucose. Results from polyphasic study suggested that strain PAMC80007T is a novel species of the genus Domibacillus for which the name Domibacillus tundrae sp. nov. is proposed. The type strain is PAMC 80007T (= JCM 30371T = KCTC 33549T = DSM 29572T). An emended description of the genus Domibacillus is also provided.