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 C18:1 ω7c and saturated C16:0. 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)).