重离子束辐照诱发阿维菌素生物代谢功能变化的机理研究；

项目名称： 重离子束辐照诱发阿维菌素生物代谢功能变化的机理研究；

项目编号： No.11305225

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 王曙阳

作者单位： 中国科学院近代物理研究所

项目金额： 30万元

中文摘要： 阿维菌素是由阿维链霉菌分泌的一种次级代谢产物，是迄今发现的高效、广谱、易降解、无残留、有效期长的生物杀虫杀螨剂之一。阿维链霉菌普遍存在发酵效价低，阿维菌素生产成本较高，限制了该生物农药的广泛使用。因此，选育高效价的菌种是发酵行业竞争的焦点。目前利用重离子束辐照选育微生物菌株，培育高转化率的发酵新菌种，已显示出明显的优势。本项目以重离子辐照选育的高效价阿维链霉菌株（效价5200μg/ml）和原始菌株（3800μg/ml）为研究对象，从分子水平研究重离子束诱发的突变点、突变基因对阿维链霉菌生物代谢影响，探讨阿维菌素关键合成基因突变及其表达变化对阿维菌素生物代谢的影响。通过本研究揭示碳离子束辐照引起阿维链霉菌代谢功能变化的机理,为基因修饰、定点基因突变改造阿维链霉菌提供依据，指导离子束诱变高产微生物菌种的选育。

中文关键词： 重离子束；诱变机理；基因突变；蛋白表达；生物代谢

英文摘要： Avermectins are a group of secondary metabolites fermentation products from Streptomyces avermitilis. It is known to be excellent anthelmintic agents with a good potency and broad spectrum of activity against a variety of nematode and anthropod parasites and a low level of side-effects on the host organism. Therefore, the breeding of high titers of bacteria is the focus of competition in the fermentation industry. It has affirmed that heavy ion beam is the effective method on breeding and cultivating new strains of high conversion rate of fermentation. This project are studied in the original strain（3800μg/ml）and the high-product strains (5200μg/ml) mutated by heavy ion irradiation. Mutations point and the mutant gene induced by heavy ion beam impact on biological metabolism of Streptomyces avermitilis are studied at the molecular level.It will explore that the impact on avermectin biological metabolism of the change in avermectin key synthetic genes and their expression. Through this research reveals that mechanism of change metabolic function on avermitilis induced by heavy ion beam irradiation.This study will provide a basis for genetically modified and site - directed mutagenesis to transform S. avermitilis, and lay the foundation for the guidance of the heavy ions in the microbial field.

英文关键词： Heavy ion beam；Mutation mechanism；Gene mutation；Protein expression；Biological metabolism