芦笋茎枯病菌细胞壁降解酶活性的测定及条件优化  

Measurement of cell wall degrading enzymes from asparagus stem blight pathogen and its optimization of activity determination conditions

作　　者：杨迎青[1] 孟凡[1,2] 兰波[1] 徐沛东[1,3] 张顺梁[1] 李湘民[1] 

机构地区：[1]江西省农业科学院植物保护研究所,南昌330200 [2]江西农业大学农学院,南昌330045 [3]江西农业大学生物科学与工程学院,南昌330045

出　　处：《华中农业大学学报》2014年第2期57-60,共4页Journal of Huazhong Agricultural University

基　　金：公益性行业(农业)科研专项(201003074);国家重点基础研究发展计划项目(2011CB111603);江西省农业科学院创新基金项目(2011CBS006)

摘　　要：为明确芦笋茎枯病菌细胞壁降解酶的活性及测定条件，利用3,5-二硝基水杨酸法（DNS法）测定7种常见细胞壁降解酶的活性，比较不同底物对3种主要酶的诱导作用，并从温度、时间、pH值等方面优化酶活性的测定条件。结果表明： 7种细胞壁降解酶中，多聚半乳糖醛酸酶（polygalacturonase,PG）的活性较高，其次是果胶甲基半乳糖醛酸酶（polymethylgalacturonase,PMG）和β-1,4-内切葡聚糖酶（endo-β-1,4-glucanase,Cx），其他4种酶活性较低。在3种主要细胞壁降解酶中，Cx以1%羧甲基纤维素钠盐（CMC）作为底物的诱导效果较好，PG和PMG以1%柑橘果胶（pectin）作为底物的诱导效果较好。Cx 的最佳反应温度是50℃， PG的最佳反应温度是50~60℃， PMG的最佳反应温度是60℃； Cx的最佳反应时间是50 min， PG和PMG的最佳反应时间是60 min； Cx和PG的最佳反应pH值是4.0， PMG的最佳反应pH值是8.0。To define the activity and optimize the determination conditions of the cell wall degrading enzymes from asparagus stem blight pathogen, the activities of 7 cell wall degrading enzymes were de- termined by the 3,5-dinitrosalicylic acid （DNS） method, the induced effects of different substrates were compared,and the determination conditions for 3 main enzymes were optimized in 3 aspects, i.e. tem- perature, time and pH value. The results revealed that in the 7 cell wall degrading enzymes the activity of polygalacturonase （PG） was the most vigorous, followed by polymethylgalacturonase （PMG） and en- do-β-1,4-glucanase （Cx）, whereas the other 4 enzymes were of lower activity. In the 3 main enzymes, 1%CMC was the better induced substrate for Cx and 1 % pectin was the better for PG and PMG. In re- garding to reaction temperature,it was found that the best reaction temperature for Cx was 50 ℃ and the best for PG and PMG was 50 -60 ℃ and 60 ℃, respectively. In regarding to reaction time,it was found that 50 min was more suitable for Cx, whereas 60 min was more suitable for PG and PMG. In regarding to pH value,it was found that pH 4. 0 was more suitable for Cx and PG, whereas pH 8. 0 was more suit- able for PMG.

关 键 词：芦笋 茎枯病菌 细胞壁降解酶 酶活性 

分 类 号：S432.44[农业科学—植物病理学] S436.44[农业科学—农业昆虫与害虫防治]