Li Kaiqin, Qian Ying, Gao Jian, Liang Wei
School of Computer Science and Engineering, Hunan University of Science and Technology, Xiangtan, PR China.
School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, PR China.
Int J Syst Evol Microbiol. 2025 Mar;75(3). doi: 10.1099/ijsem.0.006717.
Strain HUAS MG31 was isolated from the rhizosphere soil of 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 contained -diaminopimelic acid, and whole-cell sugars were galactose and mannose. The menaquinones of strain HUAS MG31 were MK-9(H), MK-9(H) and MK-9(H). The major cellular fatty acids consisted of Summed Feature 9 (-C ω9c/10-methyl C), -C, -C, -C, -C, -C, Summed Feature 3 ( H-C / ω6c) and cyclo C. Sequence analysis based on the full-length 16S rRNA gene of strain HUAS MG31 showed that it shared highest sequence similarities to HKI 0190 (99.5%) and HKI 0186 (99.4%). The phylogenomic tree shows that strain HUAS MG31 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 was most closely related to HKI 0190. However, the average nucleotide identity and the digital DNA-DNA hybridization between strain HUAS MG31 and JCM 13005 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 was significantly different from JCM 13005. Therefore, these results reveal that strain HUAS MG31 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is HUAS MG31 (=MCCC 1K09225= JCM 37022).
菌株HUAS MG31从中国桃源县采集的根际土壤中分离得到。该菌株在高氏合成1号培养基上产生白色基内菌丝和毛发棕色气生菌丝，无扩散性色素。气生菌丝分化为直形弯曲的孢子链，由表面光滑的球形或圆柱形孢子组成。菌株HUAS MG31的细胞壁肽聚糖含有二氨基庚二酸，全细胞糖为半乳糖和甘露糖。菌株HUAS MG31的甲基萘醌为MK-9(H)、MK-9(H)和MK-9(H)。主要细胞脂肪酸包括总和特征9（-C ω9c/10-甲基C）、-C、-C、-C、-C、-C、总和特征3（H-C / ω6c）和环C。基于菌株HUAS MG31全长16S rRNA基因的序列分析表明，它与HKI 0190（99.5%）和HKI 0186（99.4%）具有最高的序列相似性。系统发育树表明，菌株HUAS MG31形成一个独立的亚分支，表明它可能属于一个潜在的新物种。基于16S rRNA基因序列的系统发育树结果表明，菌株HUAS MG31与HKI 0190关系最为密切。然而，菌株HUAS MG31与JCM 13005之间的平均核苷酸同一性和数字DNA-DNA杂交分别为87.0 %/81.2%和25.8 %，低于定义新物种的95%-96%和70 %阈值。同时，表型、化学分类学特征和MALDI-TOF MS结果进一步证实，菌株HUAS MG31与JCM 13005显著不同。因此，这些结果表明菌株HUAS MG31代表了属中的一个新物种，为此提出新名称sp. nov.。模式菌株为HUAS MG31（=MCCC 1K09225=JCM 37022）。
