链霉菌IMS002的分类鉴定及其抗真菌活性物质解析

【目的】对一株分离自植物根际土壤的具有抗真菌活性的链霉菌IMS002进行菌株分类鉴定,通过活性追踪分离纯化并鉴定有机相中的活性物质。【方法】通过16S rDNA和5个不同基因(atpD,gyrB,recA,rpoB,trpB)串联聚类分析以及生理生化实验分析,对链霉菌IMS002进行菌株分类鉴定,用扫描电子显微镜观察该株链霉菌的菌丝及孢子形态,以尖孢镰刀菌(Fusarium oxysporum)为指示菌进行生物活性追踪,通过硅胶柱层析、凝胶柱层析及高压液相色谱(HPLC)对活性物质进行分离和纯化,使用液质联用高分辨质谱仪、500 MHz核磁共振波谱仪以及圆二色光谱仪确定该物质的化学结构。【结果】IMS002经初步鉴定与产二素链霉菌(Streptomycesambofaciens)具有较近的亲缘关系,其发酵液对尖孢镰刀菌具有良好的抑菌效果,经分离和纯化以及现代波谱技术分析,确定有机相中的抑菌活性组分为Borrelidin。【结论】链霉菌IMS002能够产生化合物Borrelidin,该化合物对尖孢镰刀菌具有抑制活性。

Classification of Streptomyces sp. IMS002 and identification of its antifungal metabolite

[Objective] We classified the antifungal strain Streptomyces sp. IMS002 that was isolated from the rhizosphere soil. We identified its bioactive compound in organic phase. [Methods] Through the concatenation analysis of 16S rDNA sequence and 5 concatenated sequences (atpD, gyrB, recA, rpoB and trpB), and physiological and biochemical detection, we classified Streptomyces IMS002. Besides, we observed the hyphae and spore morphology of sp. IMS002 by scanning electron microscope sp.. Using silica gel column chromatography, gel column chromatography and HPLC, we isolated and purified the active compound against Fusarium oxysporum. Furthermore, its chemical structure was determined by a liquid mass coupled high resolution mass spectrometer, a 500 MHz NMR spectrometer, and a circular dichroism spectrometer. [Results] Streptomyces sp. IMS002 had a close relationship with Streptomyces ambofaciens, and its fermentation broth had good antifungal activity against Fusarium oxysporum. With the separation and purification and modern spectrum identification, we identified this compound as Borrelidin. [Conclusion] Streptomyces sp. IMS002 produced Borrelidin that has bioactivity against Fusarium oxysporum.