摘要
从疫霉菌PhytophthorapalmivoraButler的培养滤液中分离出分子量为10．6kD的不含糖基的耐热蛋白。这种10．6kD蛋白能诱导烟草（NicotianatabacumL．）叶片发生过敏性坏死反应。而疫霉菌另一种P．melonisKatsura的培养滤液中不含这种类似蛋白，不能诱导烟草叶片发生过敏反应。利用共聚焦激光扫描显微镜，以荧光探剂FDA（fluoresceindiacetate）指示细胞活性，DCFDA（2’，7’－dichlorodihydrofluoresceindiacetate）指示H2Q2的生成，结果表明用该蛋白处理的烟草叶片的叶肉、表皮和保卫细胞，以及悬浮培养细胞在产生过敏性坏死反应之前，均有H2Q2的大量生成。推测这种10．6kD蛋白属于elicitin类激发子。
A 10. 6 kD heat resistant, proteinacious elicitor was purified from the culture filtrate of Phytophthora palmivora Butler but not from P. melonis Katsura. The 10. 6 kD elicitor is a holoprotein devoid of glycoside. It can cause hypersensitive necrosis of the detached tobacco (Nicotiana tabacum L. ) leaves 48 h post-inoculation with dosages of above 40 ug. Four cell types were investigated by using Confocal microscopy,and 2', 7' - dichlorodihydrofluorescein diacetate (DCFDA ) as a probe of H2O2 production. It was showed that oxidative burst occurred in cultured suspension cells as well as in mesophyll cells, epidermal cells and guard cells within 10 min upon the elicitor treatment. The hypersensitive cell death appeared 6 h after the treatment when inoculated with fluorescein diacetate (FDA) as indicator of cell viability. These results suggest that H2O2 accumulation was the main cause of the hypersensitive cell death in tobacco induced by the 10. 6 kD elicitor. This 10 - 6 kD elicitor may belong to the family of elicitins.
基金
国家自然科学基金!39670076
国家教委博士点基金!970101
植物病虫害生物学国家重点实验室开放基金!PD04
关键词
ELICITIN
激发子
氧化突发
过敏反应
烟草
Phytophthora palmivora, Elicitin, Elicitor,Oxidative burst,Hypersensitive response, Tobacco
