Comparative studies of the peroxidases from hairy roots of Daucus carota, Ipomoea batatas and Solanum aviculare
Comparative studies of the peroxidases from hairy roots of Daucus carota, Ipomoea batatas and Solanum aviculare
复制标题
DOI：
10.1016/j.plantsci.2004.06.015
复制
发表时间：
2004-11-01
期刊：
影响因子：
5.2
通讯作者：
Pletsch, M
中科院分区：
文献类型：
--
作者：
de Araujo, BS;de Oliveira, JO;Pletsch, M
从胡萝卜、甘薯和茄子的毛状根培养物中提取过氧化物酶的最佳条件为：EC1.11.1.7。以愈创木酚、邻苯二酚、苯酚、2-氯苯酚和2，6-二氯苯酚为还原底物，测定了它们的表观动力学常数。根提取物中过氧化物酶活性分别为2.1+/-0.05、15.1+/-0.5和7.6+/-0.2U/mg蛋白质。(APP)(M)值表明，胡萝卜和小菜蛾过氧化物酶的最佳还原剂为苯酚，而L烟草的过氧化物酶则优先选择愈创木酚。以前植物的过氧化物酶对过氧化氢表现出相似的K-M(APP)值，而来自白薯的过氧化物酶对这种底物的亲和力要低得多，无论还原酚类的性质如何。较大的K-M(APP)值表明，与其他两个物种相比，甘薯可能具有不同的同工酶图谱。毛状根过氧化物酶对苯酚、2-氯苯酚、邻苯二酚和愈创木酚的氧化能力与胡萝卜毛状根的k(SPEC)(App)值相近。甘薯毛状根的过氧化物酶对愈创木酚和2-氯苯酚的催化活性高于对儿茶酚和苯酚的催化活性，而小叶甘薯毛状根的过氧化物酶对苯酚和邻苯二酚的氧化活性更高。
The optimal conditions for the extraction of peroxidases (EC 1.11.1.7) from hairy root cultures of Daucus carota L. (carrot), Ipomoea batatas L. (sweet potato) and Solanum aviculare Forst. (kangaroo apple) and their apparent kinetic constants with guaiacol, catechol, phenol, 2-chlorophenol and 2,6-dichlorophenol as reducing substrates were determined. The peroxidase activities in these root extracts were, respectively, 2.1 +/- 0.05, 15.1 +/- 0.5 and 7.6 +/- 0.2U/mg of protein. The (app)(M) values demonstrated that phenol is the preferred reductant for the peroxidases from D. carota and S. aviculare, whilst guaiacol is favoured by the peroxidases from L batatas. The peroxidases from the former plants showed similar K-M(app) values with respect to hydrogen peroxide, whilst those from I. batatas exhibited much lower affinities for this substrate regardless of the nature of the reducing phenolics. The large K-M(app) values suggest that sweet potato may have a diverse isoenzyme profile compared with the other two species. The k(spec)(app) values demonstrated that peroxidases from hairy roots of D. carota were able to oxidize phenol, 2-chlorophenol, catechol and guaiacol with similar efficiency. Peroxidases from hairy roots of I. batatas cultures were more active with regard to guaiacol and 2-chlorophenol than to catechol and phenol, unlike peroxidases from hairy roots of S. aviculare which were more active in the oxidation of phenol and catechol.