河岸带内生烟曲霉的香豆素类抗氧化产物提高拟南芥抗涝害能力研究  

Antioxidant of Coumarin Analogues from Endophytic Aspergillus fumigatus in Riparian Zone to Improve Anti-Waterlogging Ability in Arabidopsis thaliana

作　　者：高媛 曹飞 李辉 刘士平 薛艳红 GAO Yuan;CAO Fei;LI Hui;LIU Shi-ping;XUE Yan-hong(Coll.of Life Sci.&Pharm.,Three Gorges Uni.,Yichang 443002)

机构地区：[1]三峡大学生物与制药学院,湖北宜昌443002

出　　处：《微生物学杂志》2019年第6期56-64,共9页Journal of Microbiology

基　　金：国家自然科学基金项目(31270389);国家自然科学基金应急管理项目(31540065)。

摘　　要：涝害是一种阻碍植物生长发育的水分胁迫因子,严重影响着全球的农林业生产。近年来的研究表明,生活在特殊环境下的植物内生菌可以协助宿主抵抗各种胁迫环境。前期研究从三峡河岸带灌木疏花水柏枝(Myricaria laxiflora)中分离到1株内生烟曲霉(Aspergillus fumigatus)SG-17,其抗氧化产物可以增加水稻中控制活性氧合成的关键酶NADPH氧化酶的含量,并提高其抗旱能力。为了研究该菌在植物应对水淹胁迫中的作用,通过质谱、核磁等分析方法对其抗氧化物质进行了鉴定,利用全淹法评价了其对拟南芥抗水淹胁迫的能力,并通过定量PCR对拟南芥的NADPH氧化酶Atrbohs基因家族进行了表达分析。结果显示SG-17中高抗氧化活性的物质是一种香豆素类似物(Z)-N-(4-hydroxystyryl)formamide(NFA),它可有效提高拟南芥的抗水淹能力,并显著增加水淹之后与活性氧代谢密切相关的丙二醛(MDA)、超氧化物歧化酶(SOD)和乙醇脱氢酶(ADH)的含量。进一步研究表明,NFA可以调节拟南芥AtrbohD和AtrbohF两个水淹胁迫反应基因的表达,暗示在遭受淹水胁迫的河岸带植物内生菌,可产生抗氧化产物来调节植物体的活性氧代谢路径,从而提高植物的抗涝害能力。Waterlogging is kind of coercive factor that hinders plant growth and development,and seriously affects agroforestry production worldwide.Recent studies showed that endophytic fungi coexisting in plants living in unusual environment can assist the host in resisting various coercions.In the previous study,an endogenous Aspergillus fumigatus strain SG-17 from thin-flower falsetamarisk(Myricaria laxiflora),a shrub in the Three Gorges riparian zone was isolated.Its antioxidant products could increase the content of NADPH oxidase,a pivot enzyme to improve the synthesis of ROS in rice that improves the rice drought resistance.In order to study the role of the strain SG-17 on plant in responding flood-inundation coercion,the antioxidant was characterized with MS and NMR analyses,and evaluated the ability to resist flood-inundation coercion in Arabidopsis thaliana by whole-inundation method,and analyzed the expression of Atrbohs(NADPH oxidase)gene family adopting real-time quantitative PCR.The results showed that the antioxidant substance of SG-17 was an analogue of coumarin,(Z)-N-(4-hydroxystyryl)formamide(NFA),which can effectively improve flood-inundation resistance of A.thaliana,it could significantly increase the content of malondialdehyde(MDA),superoxide dismutase(SOD),and ethanol dehydrogenase(ADH)after flood-inundation,all of which closely related to the metabolism of ROS.Further studies showed that NFA could regulate the expression of two flood-inundation response genes,AtrbohD and AtrbohF in A.thaliana,indicating that some endophytes from riparian plants subjected to flood-inundation coercion could enhance waterlogging resistance ability of plants and regulate ROS metabolism by producing antioxidants.

关 键 词：内生菌 抗氧化产物 NFA 拟南芥 涝害 

分 类 号：Q939.99[生物学—微生物学]