摘要
采用 (NH4) 2 SO4分步沉淀法 ,从水稻白叶枯病菌培养滤液中提取对水稻白叶枯病菌有机酸毒素具解毒作用的解毒蛋白粗提物 (crudedetoxificationprotein ,CDP) ,经滚动式等电聚焦电泳 (RPIE)和离子交换层析 (FPLC)分离 ,生物测定结果表明 ,第Ⅱ吸收峰具有生物活性 ;再经SDS PAGE电泳和考马斯亮蓝染色 ,第Ⅱ吸收峰收集物有明显的一条带 ,相对分子质量为 4 7 9× 10 3 。野生菌产生的CDP解毒活性明显低于其毒性基因突变体。CDP对热和蛋白酶K均不稳定 ,对毒素的解毒主要是通过脱羧起作用。用CDP处理水稻后 ,水稻体内与抗病性相关的酶活性显著提高 ;接种水稻白叶枯病菌 。
A protein isolated from Xanthomonas oryzae pv oryzae(X o o) can detoxify organic acid toxins,which is produced by X o o and play an important role in causing leaf blight of rice.The protein was purified by Rotofor TM proparature IEF electrophoresis(RPIE)and fast protein liquid chromatography(FPLC).Biochemical assays showed that the Ⅱ peak has detoxificating activities.There is one main band with SDS PAGE electrophoresis and identifies a size of 47 9×10 3 for the protein.Application of protein to rice seeds and tobacco leaves before,simultaneously with,and after treatment of the seeds and plants with organic acid toxin abolished inhibition of seeds by the toxin and the toxicity appearing in necrosis in tobacco leaves.Activity of defense related enzymes,such as PAL and PO,was increased in rice plants treated with the detoxification protein.Based on these data,we concluded that the detoxification protein contributes to plant resistance possibly by decarboxylation of the toxin and induction of activity of defense related enzymes.
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2002年第4期28-32,共5页
Journal of Nanjing Agricultural University
基金
江苏省自然科学基金 (BK970 98)
教育部博士点基金 (2 0 0 0 0 2 0 72 1)
关键词
水稻白叶枯病菌
解毒素蛋白
提纯
作用机制
有机酸毒素
等电聚集电泳
离子交换层析
Xanthomonas oryzae pv oryzae
organic acid toxins
crude detoxification protein(CDP)
Rotofor TM proparature IEF electrophoresis(RPIE)
fast protein liquid chromatography(FPLC)
mechanism of detoxification
