Abstract

Changes in the activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT) for the plants Nicotiana tabacum L. and Secale cereale L. during low-temperature hardening have been investigated. It was determined that a transient increase in the content of MDA occurs in tobacco plants at the beginning of the hardening period with subsequent activation of SOD, APX, and CAT. Unlike tobacco, winter rye has an MDA content and activity of SOD, APX, and CAT throughout the hardening period that remains at the level of unhardened plants. In tobacco cells, the majority of SOD activity was detected in chloroplasts (90%), while other cellular structures accounted for only 10% of the total activity identified in PAGE. In winter rye cells, SOD activity was distributed evenly between chloroplasts and other cellular compartments (46% in chloroplasts and 54% outside of chloroplasts). The distribution of APX and CAT activity in tobacco and winter rye cells was identical: all APX was concentrated in chloroplasts, while all catalase activity was manifested outside of chloroplasts. It is concluded that tobacco and winter rye plants showed different antioxidant defense strategies under conditions of low hardening temperatures. Tobacco plants provided protection against oxidative damage during low-temperature hardening by increasing activity of SOD, APX, and CAT. Winter rye plants were able to avoid the development of oxidative stress during hardening due to uniform distribution of SOD activity in cells, maintaining the constitutive activity of SOD, APX, and CAT, and, probably, due to the accumulation of nonenzymatic antioxidants.

中文翻译：

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烟草和小黑麦的低温硬化过程中抗氧化酶活性的变化。

摘要

植物烟草和黑麦谷物超氧化物歧化酶（SOD），抗坏血酸过氧化物酶（APX）和过氧化氢酶（CAT）活性的变化已经研究了低温硬化过程中的L.。已确定，在硬化期开始时，随着SOD，APX和CAT的活化，MDA含量在烟草植物中发生了短暂的增加。与烟草不同，黑麦在整个硬化期间的MDA含量和SOD，APX和CAT的活性都保持在未硬化植物的水平。在烟草细胞中，大部分的SOD活性在叶绿体中检测到（90％），而其他细胞结构仅占PAGE中鉴定的总活性的10％。在冬季黑麦细胞中，SOD活性均匀分布在叶绿体和其他细胞区室之间（叶绿体中46％，叶绿体外部54％）。烟草和黑麦细胞中APX和CAT活性的分布相同：所有的APX都集中在叶绿体中，而所有过氧化氢酶的活性都在叶绿体之外表现出来。结论是，在低硬化温度下，烟草和黑麦植物表现出不同的抗氧化防御策略。烟草植物通过增加SOD，APX和CAT的活性，为低温硬化过程中的氧化损伤提供了保护。冬季黑麦植物能够避免由于硬化过程中细胞中SOD活性的均匀分布，保持SOD，APX和CAT的本构活性以及可能由于非酶抗氧化剂的积累而在硬化过程中产生氧化应激。结论是，在低硬化温度下，烟草和黑麦植物表现出不同的抗氧化防御策略。烟草植物通过增加SOD，APX和CAT的活性，为低温硬化过程中的氧化损伤提供了保护。冬季黑麦植物能够避免由于硬化过程中细胞中SOD活性的均匀分布，保持SOD，APX和CAT的本构活性以及可能由于非酶性抗氧化剂的积累而在硬化过程中产生氧化应激。结论是，在低硬化温度下，烟草和黑麦植物表现出不同的抗氧化防御策略。烟草植物通过增加SOD，APX和CAT的活性，为低温硬化过程中的氧化损伤提供了保护。冬季黑麦植物能够避免由于硬化过程中细胞中SOD活性的均匀分布，保持SOD，APX和CAT的本构活性以及可能由于非酶性抗氧化剂的积累而在硬化过程中产生氧化应激。