Three strains isolated from the soil of a garden in Tokyo, Japan, were characterized physiologically, biochemically and in terms of fatty acid profile, DNA-DNA relatedness and 16S rRNA gene sequence. The isolates were Gram-negative, aerobic, rod-shaped cells with polar flagellation. According to DNA-DNA similarity, the strains belonged to the same species. The bacteria grew at temperatures from 10 to 37 degrees C, with an optimum around 25-30 degrees C. Growth was observed at pH values from 5.6 to 8.0. The DNA G+C content ranged from 63.4 to 64.0 mol%. Phylogenetic analyses of 16S rRNA gene sequences revealed a clear affiliation with members of the family 'Xanthomonadaceae'. The closest relationship was seen with Fulvimonas soli and Frateuria aurantia, but, in terms of physiology and fatty acid profile, the bacteria described were rather distant from Fulvimonas and Frateuria. On the basis of phenotypic and phylogenetic distinctness, it is proposed that the isolates represent a novel species in a novel genus, namely Dyella japonica gen. nov., sp. nov. The type strain is XD53(T) (=IAM 15069(T)=DSM 16301(T)=ATCC BAA-939(T)).