Chaman M E, Corcuera L J, Zúñiga G E, Cardemil L, Argandoña V H
Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile.
J Agric Food Chem. 2001 May;49(5):2249-53. doi: 10.1021/jf0011440.
Peroxidase enzymes have been found in soluble, ionically bound, and covalently bound forms and have been implicated in several physiological processes in plants. This paper investigates the effect of aphid infestation on soluble and bound-cell wall peroxidase activity and bound-cell wall isoform changes of barley plants. Peroxidase activity was measured in control plants and plants infested with the aphid Schizaphis graminum (Rondani). The activity of soluble peroxidases increased with time of infestation, older plants being more affected than younger ones. The increase in bound-cell wall peroxidase activity as a function of age was higher in infested than in control plants, being higher in ionically bound than in covalently bound peroxidases. When the aphids were removed from plants, the activities of both types of peroxidases decreased to control levels. Isoelectrofocusing analyses of the ionically bound peroxidases showed changes in the isoform pattern. A new isoform was induced by infestation. The activities of all covalently bound isoforms increased after infestation. The physiological implications of these changes are discussed.
过氧化物酶已被发现有可溶形式、离子结合形式和共价结合形式，并参与植物的多种生理过程。本文研究了蚜虫侵染对大麦植株可溶和结合细胞壁过氧化物酶活性以及结合细胞壁同工型变化的影响。测定了对照植株和被麦二叉蚜（Rondani）侵染的植株中的过氧化物酶活性。可溶过氧化物酶的活性随侵染时间增加，较老植株比年轻植株受影响更大。侵染植株中结合细胞壁过氧化物酶活性随年龄增长的增加幅度高于对照植株，离子结合过氧化物酶的增加幅度高于共价结合过氧化物酶。当蚜虫从植株上移除后，两种过氧化物酶的活性均降至对照水平。对离子结合过氧化物酶的等电聚焦分析显示同工型模式发生了变化。侵染诱导产生了一种新的同工型。侵染后所有共价结合同工型的活性均增加。讨论了这些变化的生理意义。
