玉米大斑病菌的胞外黑色素种类及影响其产量的因素  

Determination and Characterization of Extracellular Melanin from Setosphaeria turcica and Influencing Factors of Its Production

作　　者：吴楠[1] 李青为[2] 曹志艳[1] 张娇[2] 郝志敏[1] 董金皋[1] 

机构地区：[1]河北农业大学生命科学学院/真菌毒素与植物分子病理学实验室,河北保定071000 [2]中国科学院植物研究所,北京100093

出　　处：《中国农业科学》2013年第5期927-933,共7页Scientia Agricultura Sinica

基　　金：国家自然科学基金项目(31101402);河北省自然科学基金项目(C2011204066)

摘　　要：【目的】对玉米大斑病菌胞外黑色素的种类进行确定,探索影响玉米大斑病菌野生型菌株胞外黑色素产量的因素。【方法】利用酸碱沉淀法提取玉米大斑病菌01-23(野生型)菌株和1,3,8-三羟基萘还原酶(3HNR)基因缺失突变菌株ΔSt3hnr-3的胞外黑色素,采用红外光谱分析确定黑色素的种类。通过在培养基中添加不同的物质,确定影响胞外黑色素产量的因素。【结果】玉米大斑病菌胞外黑色素不同于DHN黑色素,2种黑色素的理化性质相似,溶解于热碱溶液,且与FeCl3反应产生沉淀。在振荡培养条件下,加入酪氨酸和三环唑分别使胞外黑色素的产量提高了2倍和1.5倍,而Cu2+浓度低于0.5μmol.L-1利于胞外黑色素的合成,反之则表现抑制作用;pH值为6时较利于对胞外黑色素分泌。【结论】玉米大斑病菌胞外黑色素为DOPA黑色素类型,酪氨酸和三环唑对胞外黑色素的产生具有明显促进作用。[Objective] The objective of this study is to determine the type ofextracellular melanin from Setosphaeria turcica and explore the influencing factors of its production to lay a foundation for further clarification of the relationship between melanin and pathogenicity. [Method] Acid precipitation method was used to extract the extracellular melanin of 01-23 and ASt3hnr-3 strain. The type of melanin was preliminarily identified with infrared spectroscopy. Media containing tyrosine, tricyclazole, Cu2＋.and different pH values were used to determine the influences of these factors on the production of extracellular melanin. [ Result ] The infrared spectroscopy of extracellular melanin in S. turcica was different from the DHN melanin, while the physical and chemical properties of the samples from both strains were similar. It could dissolve in hot alkaline solution and produce precipitation when it was reacted with FeCl3. Under the shaking culture, the contents of extracellular melanin in the culture filtrates respectively containing tyrosine and tricyclazole were about 2 and 1.5 times more than that of the mock, while it could also be slightly enhanced by Cu2＋ with the concentration lower than 0.5μmol.L-1 or at pH6.0. [Conclusion] The extracellular melanin from S. turcica was proved to be similar with DOPA melanin. Tyrosine and tricyclazole obviously promoted the production of extracellular melanin.

关 键 词：玉米大斑病菌 DOPA黑色素 红外光谱 

分 类 号：S435.131[农业科学—农业昆虫与害虫防治]