PDF(Pubmed)
Abstract：
Taxus spp. are ancient tree species that have survived from the Quaternary glacier period, and their metabolites, such as taxol, have been used as anticancer drugs globally. Plant-endophytic microbial interaction plays a crucial role in exerting a profound impact on host growth and secondary metabolite synthesis. In this study, high-throughput sequencing was employed to explore endophytic microbial diversity in the roots, stems, and leaves of the Taxus yunnanensis (T. yunnanensis). The analysis revealed some dominant genera of endophytic bacteria, such as Pseudomonas, Neorhizobium, Acidovorax, and Flavobacterium, with Cladosporium, Phyllosticta, Fusarium, and Codinaeopsis as prominent endophytic fungi genera. We isolated 108 endophytic bacteria and 27 endophytic fungi from roots, stems, and leaves. In vitro assays were utilized to screen for endophytic bacteria with growth-promoting capabilities, including IAA production, cellulase, siderophore production, protease and ACC deaminase activity, inorganic phosphate solubilization, and nitrogen fixation. Three promising strains, Kocuria sp. TRI2-1, Micromonospora sp. TSI4-1, and Sphingomonas sp. MG-2, were selected based on their superior growth-promotion characteristics. These strains exhibited preferable plant growth promotion when applied to Arabidopsis thaliana growth. Fermentation broths of these three strains were also found to significantly promote the accumulation of taxanes in T. yunnanensis stem cells, among which strain TSI4-1 demonstrated outstanding increase potentials, with an effective induction of taxol, baccatin III, and 10-DAB contents. After six days of treatment, the contents of these metabolites were 3.28 times, 2.23 times, and 2.17 times the initial amounts, reaching 8720, 331, and 371 ng/g of dry weight of stem cells, respectively. These findings present new insight into the industrialization of taxol production through Taxus stem cell fermentation, thereby promoting the conservation of wild Taxus resources by maximizing their potential economic benefits.
摘要：
Taxusspp.是从第四纪冰川时期幸存下来的古老树种，以及它们的代谢物，比如紫杉醇,已在全球范围内用作抗癌药物。植物-内生微生物相互作用对寄主生长和次生代谢产物的合成产生深远的影响。在这项研究中,采用高通量测序技术探索根中内生微生物的多样性，茎,和云南红豆杉的叶子(T.云南）。分析揭示了一些内生细菌的优势属，如假单胞菌，新根瘤菌,Acidovorax,和黄杆菌,有枝孢菌,Phyllosticta,镰刀菌,和棘藻是突出的内生真菌属。我们从根中分离出108个内生细菌和27个内生真菌，茎,和树叶。体外试验用于筛选具有生长促进能力的内生细菌，包括IAA生产，纤维素酶,铁载体生产，蛋白酶和ACC脱氨酶活性，无机磷酸盐溶解，和固氮。三个有前途的菌株，Kocuriasp.TRI2-1，小单孢菌属。TSI4-1和鞘氨醇单胞菌。基于其优异的生长促进特性选择MG-2。当应用于拟南芥生长时，这些菌株表现出更好的植物生长促进作用。还发现这三个菌株的发酵液显着促进紫杉烷在云南芥干细胞中的积累，其中菌株TSI4-1表现出突出的增加潜力，有效诱导紫杉醇，baccatinIII,和10-DAB内容。经过六天的治疗,这些代谢物的含量是3.28倍，2.23倍，是初始金额的2.17倍，达到8720、331和371ng/g干细胞干重，分别。这些发现为通过红豆杉干细胞发酵生产紫杉醇的工业化提供了新的见解，从而促进野生红豆杉资源的保护，使其潜在的经济效益最大化。
