受损复叶槭中酯氧合酶的生化特征及其活性变化

Biochemical Characters and Activity Changes of Lipoxygenase in Damaged Acer negundo

对被机械损伤或天牛咬食后,复叶槭叶片中酯氧合酶的生化特征及其活性变化进行了研究。结果表明:在不同温度和pH值条件下,受损植株中酯氧合酶的活性均高于对照,并且酯氧合酶的最适温度为25℃,最适pH值为7.0。在植株受损后的72h内,酯氧合酶米氏常数最低,活性最高。这表明,复叶槭通过激活酯氧合酶途径,对不同形式的损伤作出了反应。

An experiment was conducted to study the biochemical characters and activity changes of lipoxygenase in damaged Acer negundo L. with mechanical wounding or fed by long-horned beetle. Result shows that lipoxygenase activities in the damaged plants under different temperatures and pH values tend to be higher compared with the control. The optimal temperature of lipoxygenase is 25 degrees C and the optimum pH is 7.0. The Michaelis constant of lipoxygenase reaches a minimal value and the activity of lipoxygenase is maximal within 72 hours after damage. It indicates that Acer negundo responds to different damages by lipoxygenase pathway.