Dyella acidisoli sp nov., D-flagellata sp nov and D-nitratireducens sp nov., isolated from forest soil

Bacterial strains 4M-Z03(T), 4M-K16(T) and DHG59(T) were isolated from forest soil samples collected from the Dinghushan Biosphere Reserve, Guangdong Province, PR China (112 degrees 31' E 23 degrees 10' N). The three strains grew well at 28 degrees C, pH 5.0-6.0 on R2A medium. On the basis of 16S rRNA gene sequence analysis, the three strains, together with Dyella humi DHG40(T), formed a distinct phyletic clade within the genus Dyella, and the sequence similarities between any strains of the clade ranged from 97.8 to 98.5 %. Sequence analysis of concatenated partial gyrB, lepA and recA gene sequences also strongly suggested that the three strains represented three novel species of the genus Dyella. The respiratory lipoquinone of the three strains was ubiquinone-8, and their DNA G+C content was 58.2-59.0 mol%. The fatty acid profiles differed substantially among these three strains, although they had two common major fatty acids, iso-C-15:0 and iso-C-17:1 omega 9c. The DNA-DNA relatedness among the three strains and the type strains of the closest species of the genus Dyella examined was lower than 50 %. The results of genotypic and phenotypic characterization presented above demonstrate that the three strains examined represent three novel species of the genus Dyella, for which the names Dyella acidisoli sp. nov. (type strain 4M-Z03(T) = NBRC 111980(T) = KCTC 52131(T)), Dyella flagellata sp. nov. (type strain 4M-K16(T) = NBRC 111981(T) = KCTC 52130(T)) and Dyella nitratireducens sp. nov. (type strain DHG59(T) = NBRC 111472(T) = LMG 29201(T) = CGMCC 1.15439(T)) are proposed.