基于真菌激发子调控的桑黄活性多糖分子链空间构象研究

项目名称： 基于真菌激发子调控的桑黄活性多糖分子链空间构象研究

项目编号： No.31501815

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 农业科学

项目作者： 程俊文

作者单位： 浙江省林业科学研究院

项目金额： 19万元

中文摘要： 天然名贵食药真菌桑黄具有较强的免疫调节活性，其面临的野生资源匮乏瓶颈问题可通过液体发酵获得其次生代谢产物加以解决。近年来，通过添加真菌激发子等外源刺激物诱导食药真菌多糖类有效成分的合成已经成为真菌发酵调控研究的热点。前期的研究表明，真菌激发子可有效促进桑黄液体发酵多糖的含量和生物活性，然而关于其对桑黄多糖液体发酵合成调控的机理及其多糖空间构象的影响尚未见报道。基于此，本项目通过转录组技术比较在真菌激发子调控下的真菌RNA表达水平的变化，同时，测定合成途径中关键酶α-葡糖磷酸变位酶和葡糖磷酸异构酶的酶活变化，分别从分子水平上研究真菌激发子对桑黄多糖合成关键酶基因表达和蛋白表达水平的调控作用。同时，通过动静态激光光散射、原子力显微镜等技术对真菌激发子调控桑黄发酵并经纯化的活性多糖纯品FPIEPS-I进行精细结构及其空间构象的表征，以此阐明真菌激发子对高活性桑黄多糖生物合成调控的机理。

中文关键词： 桑黄；真菌激发子；代谢调控；多糖；构象

英文摘要： Phellinus igniarius is one of the most well-known medicinal mushrooms in traditional Chinese medicine. The polysaccharide of Phellinus igniarius has been reported to present obvious immunomodulatory activity. The immunomodulatory activity of fungi polysaccharide could be stimulated by recognition of macrophages and its activity is supposed to be with the certain advanced structure, such as chain conformation, mechanical property and dynamics performance. Up to now, employment of pathogenic and non-pathogenic fungal preparations and chemicals, termed as elicitors, thus becomes one of the most important strategies to improve secondary metabolite production in cell cultures. Fungal elicitors were induced to cell culture process at the later-stage of exponential growth phase, which was proved to be an effective way to increase the production and productivity of secondary metabolites. However, no study has been reported on the synthetic mechanism of phellinus igniarius polysaccharide which is regulated by elicitors. Besides, there is few literature on the relationship between structure-activity and the active polysaccharide from Phellinus igniarius which is regulated by fungal elicitor. . In this project, we would analyse the activity ofα-PGM and PGI, studying the change of RNA expression by transcriptome. Then the effect of fungal elicitor on gene expression and protein expression during polysaccharide synthesis would be studied. We would combine the theory of polymer solution, single molecule force spectroscopy and molecular biology to analyze the structure-immunomudulatory activity with the help of laser light scattering and atomic force microspectroscopy. The relationship of chain conformation and immune activity would be elucidated..This work is useful to understand the mechanism of phellinus-igniarius polysaccharide biosynthesis. It will lay a theoretical foundation for directional preparation of high bioactive polysaccharide.

英文关键词： Phellinus igniarius;fungal elicitor; metabolic regulation;Polysaccharide;conformation