Sphingobacterium endophyticum sp. nov., a novel endophyte isolated from halophyte

A bacterial strain designated NYYP31T was isolated from the leaves of an annual halophytes, Suaeda corniculata Bunge, collected from the southern edge of the Gurbantunggut desert, north-west China. Strain NYYP31T was Gram-staining negative, strictly aerobic, rod-shaped, non-motile, and non-spore-forming. Growth was observed at 4–42 °C, at pH 5.0–10.0, in the presence of up to 8% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and coding sequences of 92 protein clusters showed that strain NYYP31T should be assigned to the genus Sphingobacterium. 16S rRNA gene sequence similarity analysis showed that strain NYYP31T was most closely related to the type strain of Sphingobacterium daejeonense (97.9%) and Sphingobacterium lactis (97.7%). The predominant isoprenoid quinone was MK-7. The major fatty acids were identified as iso-C15:0, iso-C17:0 3-OH and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). The polar lipids were phosphatidylethanolamine, two unidentified phospholipids, three unidentified lipids, three unidentified amino phospholipids, and two unidentified glycolipids. The genomic DNA G + C content was 36.4 mol%. The average nucleotide identity (ANI) values for strain NYYP31T to the type strains of S. daejeonense and S. lactis were 77.9 and 74.1%, respectively, which were below the cut-off level (95–96%) for species delineation. Based on the above results, strain NYYP31T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium endophyticum sp. nov. is proposed. The type strain is NYYP31T (= CGMCC 1.16979T = NBRC 114258T).