Sphingomonas agri sp. nov., a bacterium isolated from soil.

A Gram-reaction-negative, aerobic, non-motile, white (translucent) and rod-shaped bacterium (designated HKS-06) isolated from soil was characterized by a polyphasic approach to clarify its taxonomic position. Strain HKS-06 was observed to grow optimally at 30 °C and at pH 6.5-7.0 on R2A agar medium. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HKS-06 belongs to the genus Sphingomonas and is most closely related to Sphingomonas lutea JS5 (97.4 % similarity). The G+C content of the genomic DNA was 64.1 mol%. Chemotaxonomic data [major quinone (Q-10), major polar lipids (phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, phosphatidylcholine, unknown polar lipid) and major fatty acids (summed feature 8, comprising C18 : 1ω7c/ω6c and/or C18 : 1ω6c, C18 : 0 3-OH and C16 : 0)] supported the affiliation of strain HKS-06 to the genus Sphingomonas. Moreover, the physiological and biochemical results and low level of DNA-DNA relatedness [between strain HKS06 and S. lutea JS5 (20.24±1.2 %)] allowed the phenotypic and genotypic differentiation of strain HKS-06 from recognized species of the genus Sphingomonas. The new isolate therefore represents a novel species, for which the name Sphingomonas agri sp. nov. is proposed. The type strain is HKS-06 (=KACC 18880=LMG 29563).