Department of Biological Sciences, Union College, Schenectady, New York 12308.
Plant Physiol. 1974 Apr;53(4):569-74. doi: 10.1104/pp.53.4.569.
In tobacco (Nicotiana Tabacum) pith, sweet potato (Ipomoea batatas), and carrot (Daucus carota) storage roots, differences were found between cell wall and protoplast peroxidases in their isoenzyme patterns, activity, and reaction to tissue injury.In the pith of elongating tobacco internodes, 90% of total activity was associated with the walls, 80% of which was due to the ionically and covalently bound fractions. With senescence, the increase in activity occurred mainly in the protoplast and the free fraction in the walls. The major protoplast isoperoxidases formed the free wall fraction, and the minor ones formed the wall bound fractions. The minor isoperoxidases were the only ones whose activities were affected by cut injury. Neither senescence nor injury caused qualitative changes in the cell isoperoxidase pattern. In the potato root cells, the isoperoxidases were also distinctive in their distribution and in their reactions to injury as well as to ethylene.In potato and carrot roots, the wall fractions contributed 30 and 95%, respectively, to total peroxidase activity. The injury-induced increase in peroxidase activity occurred mainly in the protoplast of tobacco pith and potato roots and almost entirely in the ionically bound fraction of the walls in carrot roots. Ethylene stimulated peroxidase development in potato roots, especially in the protoplast, but had no effect in either tobacco pith or carrot roots. Ethylene did not affect the inhibiting action of indoleacetic acid on peroxidase activity in tobacco pith, nor did indoleacetic acid significantly affect the stimulating action of ethylene in potato roots.Actinomycin D inhibited the injury-dependent development of peroxidase in tobacco pith, stimulated the injury- and ethylene-dependent peroxidase development in potato root, and had no effect on peroxidase development in carrot root. Cycloheximide prevented the increase in peroxidase activity in tobacco pith and potato root, but not in the carrot root. Thus, the enhancement of peroxidase activity resulted from either enzyme activation exclusively or from enzyme synthesis. RNA synthesis seems to be only indirectly related to isoperoxidase synthesis caused by injury or ethylene.
在烟草（Nicotiana Tabacum）髓、番薯（Ipomoea batatas）和胡萝卜（Daucus carota）块根中，细胞壁和原生质体过氧化物酶在同工酶图谱、活性和对组织损伤的反应方面存在差异。在伸长的烟草节间髓中，90%的总活性与细胞壁相关，其中 80%归因于离子结合和共价结合部分。随着衰老，活性的增加主要发生在原生质体和细胞壁的游离部分。主要的原生质体同工过氧化物酶形成了游离壁部分，而较小的同工过氧化物酶形成了壁结合部分。只有较小的同工过氧化物酶的活性受到切割损伤的影响。衰老和损伤都没有导致细胞同工过氧化物酶图谱的定性变化。在马铃薯根细胞中，同工过氧化物酶在分布和对损伤以及乙烯的反应方面也具有独特性。在马铃薯和胡萝卜根中，壁部分分别贡献了 30%和 95%的总过氧化物酶活性。损伤诱导的过氧化物酶活性增加主要发生在烟草髓和马铃薯根的原生质体中，而在胡萝卜根的细胞壁离子结合部分几乎完全发生。乙烯刺激马铃薯根的过氧化物酶发育，特别是在原生质体中，但在烟草髓或胡萝卜根中没有影响。乙烯对吲哚乙酸抑制烟草髓过氧化物酶活性的作用没有影响，吲哚乙酸也没有显著影响乙烯对马铃薯根的刺激作用。放线菌素 D 抑制烟草髓中依赖损伤的过氧化物酶发育，刺激马铃薯根中依赖损伤和乙烯的过氧化物酶发育，对胡萝卜根的过氧化物酶发育没有影响。环己亚胺防止烟草髓和马铃薯根中过氧化物酶活性的增加，但不能防止胡萝卜根中的过氧化物酶活性的增加。因此，过氧化物酶活性的增强是由于酶的激活或酶的合成。RNA 合成似乎与损伤或乙烯引起的同工过氧化物酶合成仅间接相关。
