Sphingomonas panaciterrae sp. nov. a plant growth-promoting bacterium isolated from soil of a ginseng field

Strain DCY91^T, a Gram-stain-negative, rod-shaped, aerobic, non-motile bacterium, was isolated from soil of ginseng field in Gyeonggi province, South Korea. Strain DCY91^T shared the highest 16S rRNA gene sequence similarity with Sphingomonas mucosissima DSM 17494^T (98.55 %), Sphingomonas dokdonensis KACC 17420^T (98.11 %) and Sphingomonas xinjiangensis DSM 26736^T (96.68 %). The strain DCY91^T was found to able to grow best in trypticase soy agar at 28 °C, at pH 7 and at 0.5 % NaCl. Ubiquinone 10 was identified as the isoprenoid quinone. The major polar lipids were identified as sphingoglycolipid, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The major fatty acids of strain DCY91^T were identified as unsaturated C_18:1ω7c and saturated C_16:0. The major polyamine content was sym-homospermidine. The DNA G + C content was determined to be 65.8 mol% (HPLC). After 6 days of incubation, strain DCY91^T produced 9.64 ± 1.73 and 33.73 ± 4.66 µg/ml indole-3-acetic acid, using media without l-tryptophan and supplemented with l-tryptophan, respectively. Strain DCY91^T was also weakly solubilized phosphate and produced siderophores. On the basis of the phenotypic characteristics, genotypic analysis and chemotaxonomic characteristics, strain DCY91^T is considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas panaciterrae sp. nov. is proposed. The type strain is DCY91^T (=KCTC 42346^T =JCM 30807^T).