Kitasatospora camelliae sp. nov., isolated from rhizosphere soil of Camellia oleifera

Strain HUAS MG31^T was isolated from the rhizosphere soil of <i>Camellia oleifera</i> collected from Taoyuan County, China. This strain produced white substrate mycelium and hair brown aerial mycelium without diffusible pigment on the Gause's synthetic No. 1 medium. Aerial mycelia differentiated into rectiflexible spore chains consisting of spherical or cylindrical spores with smooth surfaces. Cell wall peptidoglycan of strain HUAS MG31^T contained <i>meso</i>-diaminopimelic acid, and whole-cell sugars were galactose and mannose. The menaquinones of strain HUAS MG31^T were MK-9(H₆), MK-9(H₈) and MK-9(H₄). The major cellular fatty acids consisted of Summed Feature 9 (<i>iso</i>-C_{17 : 1} ω9c/10-methyl C_{16 : 0}), <i>iso</i>-C_{16 : 0}, <i>iso</i>-C_{15 : 0}, <i>anteiso</i>-C_{15 : 0}, <i>iso</i>-C_{17 : 0}, <i>anteiso</i>-C_{17 : 0}, Summed Feature 3 (<i>iso</i> H-C_{16 : 1} /_{C16 : 1} ω6c) and cyclo C_{17 : 0}. Sequence analysis based on the full-length 16S rRNA gene of strain HUAS MG31^T showed that it shared highest sequence similarities to <i>Kitasatospora paranensis</i> HKI 0190^T (99.5%) and <i>Kitasatospora terrestris</i> HKI 0186^T (99.4%). The phylogenomic tree shows that strain HUAS MG31^T forms an independent subclade, indicating that it might belong to a potential novel species. The results from phylogenetic trees based on 16S rRNA gene sequences showed that strain HUAS MG31^T was most closely related to <i>K. paranensis</i> HKI 0190^T. However, the average nucleotide identity and the digital DNA-DNA hybridization between strain HUAS MG31^T and <i>K. paranensis</i> JCM 13005^T were 87.0 %/81.2% and 25.8 %, respectively, below the 95%-96% and 70 % threshold that defined a new species. Meanwhile, phenotypic, chemotaxonomic characteristics and MALDI-TOF MS results further confirmed that strain HUAS MG31^T was significantly different from <i>K. paranensis</i> JCM 13005^T. Therefore, these results reveal that strain HUAS MG31^T represents a novel species of the genus <i>Kitasatospora</i>, for which the name <i>Kitasatospora camelliae</i> sp. nov. is proposed. The type strain is HUAS MG31^T (=MCCC 1K09225^T= JCM 37022^T).