Polyphasic assignment of an aromatic-degrading Pseudomonas sp., strain DJ77, in the genus Sphingomonas as Sphingomonas chungbukensis sp nov.

Pseudomonas sp. strain DJ77, which was described as an aromatic-degrading b acterium, was investigated to clarify its taxonomic position. Phylogenetic analysis based on 16S rDNA sequences indicated that the strain belonged to the genus Sphingomonas and formed a monophyletic clade with the type strain s of Sphingomonas chlorophenolica. Sphingomonas herbicidovorans and Sphingo monas yanoikuyae with sequence similarity values of 98.1, 96.1 and 95.6 %, respectively. Genomic relatedness based on DNA-DNA hybridization of strain DJ77 to these strains is 7-14%. Strain DJ77 contained ubiquinone 10 as the main respiratory quinone, and the G+C content of DNA was 63 mol%. The organ ism contained octadecenoic acid (67 %) as major cellular fatty acid. Strain DJ77 can be readily differentiated from representative members of the genu s Sphingomonas using a battery of biochemical tests. On the basis of polyph asic evidence, it is proposed that strain DJ77. previously known as Pseudom onas sp., be reclassified in the genus Sphingomonas as Sphingomonas chungbu kensis sp. nov. The type strain is strain DJ77(T)(= KCTC 2955(T) = IMSNU 11 152(T)).