Terrihabitans rhizophilus sp. nov., isolated from the rhizosphere soil of plant in temperate semi-arid steppe

Abstract The bacterial strain was isolated from the rhizosphere of Elymus dahuricus Turcz. in temperate semi-arid steppe, located in the northern of Inner Mongolia Autonomous Region, China. Strain PJ23 T is Gram-stain-negative, aerobic, light-pink, short rod-shaped, and does not form spores. Cell growth could be observed at 4-29 ℃ (optimum, 24 ℃), pH 6.0-8.6 (optimum, 8.0) and in the presence of 0-5 % (w/v) NaCl (optimum, 2.5 %). The major fatty acids of strain PJ23 T were Summed feature 8 (C 18:1 ω 6c and/or C 18:1 ω 7c ) 39.42 %) and C 16:0 (9.60 %). The polar lipid profile was composed of phosphatidylcholine, two unidentified glycolipids, one unidentified aminophospholipid, and two other unidentified polar lipids. The sole respiratory quinone was ubiquinone-10. Phylogeny on full length of 16S rRNA gene sequences retrieved from the genomes showed that, the strain was closely related to Terrihabitans soli IZ6 T and Flaviflagellibacter deserti SYSU D60017 T with the sequence similarities of 96.79% and 96.15%, respectively. The G+C content was 65.23 mol% calculated on draft genome sequencing. Between the strains PJ23 T and T. soli IZ6 T , the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) was 73.39 % and 15.7 %, these values are lower than the proposed and generally accepted species boundaries of dDDH and ANI. Based on phenotypic, chemotaxonomic, and phylogenetic characteristics, strain PJ23 T represents a novel species of Terrihabitans , for which the name Terrihabitans rhizophilus sp. nov. is proposed. The type strain is PJ23 T (= KCTC 92977 T =CGMCC 1.61577 T ).