Sphingomonas flavescens sp. nov., isolated from soil.

An aerobic bacterium, designated as PT-12, was isolated from soil collected from agriculture field, and its taxonomic position was validated through a comprehensive polyphasic methodology. The strain was identified as Gram-stain-negative, non-motile, rod-shaped, and catalase- and oxidase-positive. The yellow-colored colonies showed growth ability at temperature range of 18-37 °C, NaCl content of 0-1.0% (w/v), and at a pH of 6.0-8.0. The 16S rRNA gene and phylogenetic analysis showed that strain PT-12 affiliated with the genus Sphingomonas in the family Sphingomonadaceae, and displayed the highest 16S rRNA nucleotide sequence similarity with Sphingomonas limnosediminicola 03SUJ6 (98.4%). The genome size of strain PT-12 was 2,656,862 bp and the DNA G + C content estimated from genome was 63.5%. The highest values of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) were observed between strain PT-12 and Sphingomonas segetis YJ09, accounting to 76.2% and 20.2%, respectively. In addition, both ANI and dDDH values between strain PT-12 and other phylogenetically related neighbors ranged between 69.6% and 76.2% and 18.4% and 20.2%, respectively. Chemotaxonomic features exhibited Q-10 as the only ubiquinone; homospermidine as the major polyamine; summed feature 8 (Cω7c and/or Cω6c), C, and 10-methyl C as the notable fatty acids; and phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, and sphingoglycolipid as dominating polar lipids. Overall, the comprehensive polyphasic data supported that strain PT-12 represents a novel bacterial species within the genus Sphingomonas. Accordingly, we propose the name Sphingomonas flavescens sp. nov. The type strain is PT-12 (= KCTC 92114 = NBRC 115717).