Biochemical changes in barley plants after excessive supply of copper and manganese
Biochemical changes in barley plants after excessive supply of copper and manganese
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DOI：
10.1016/j.envexpbot.2004.02.004
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发表时间：
2004-12-01
影响因子：
5.7
通讯作者：
Feller, U
中科院分区：
文献类型：
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作者：
Demirevska-Kepova, K;Simova-Stoilova, L;Feller, U
本研究采用免疫印迹技术研究了Cu、Mn胁迫下大麦叶片中与CO2固定、NH 4+同化以及抗氧化防御有关的重要蛋白质（Rubisco、Rubisco活化酶（RA）、Rubisco结合蛋白（RBP））的变化。CV.奥布佐尔）。测定了超氧化物歧化酶（SOD）、抗坏血酸过氧化物酶（APX）、愈创木酚过氧化物酶（GPX）和过氧化氢酶（CAT）的活性和同工酶谱，以及抗坏血酸（ASC）、非蛋白巯基、过氧化氢和蛋白质氧化损伤的水平。数据相关的铜或锰在叶片中的积累后，5天的营养液中的重金属（HM）过量供应。在最高的铜过量（1500 μ M），Rubisco LS和SS显着减少，而在最高的锰浓度（18,300 μ M）下，只有微小的变化，Rubisco亚基检测。在最高浓度的Cu或Mn下，RBP降低。铜、锰对RA的毒害作用不同。在高浓度Cu胁迫下，GS含量降低，GOGAT缺失。在Mn过量时，Fd-GOGAT减少，而GS没有明显变化。毒性症状的发展对应于Cu或Mn在叶片中的积累和蛋白质羰基化的逐渐增加，SOD活性降低，CAT和GPX活性升高。APX活性降低锰毒性和铜过量下没有改变。一般而言，两种毒性下同工酶谱的变化相似。仅在Mn过量时观察到H2 O2的积累。当比较两种毒性时，检测到低分子抗氧化剂的对比变化。Cu过量主要影响非蛋白SH基团，而Mn影响ASC含量。铜或锰毒性下的氧化应激是最有可能的结果，低分子抗氧化剂，因为它们参与解毒过程和抗氧化酶的失衡耗尽。本文讨论了重金属在叶片中积累，导致不同的显示氧化胁迫，并在个别叶绿体蛋白质的变化之间的联系。(C)2004 Elsevier B. V.保留所有权利。
The present study was undertaken to identify changes in some important proteins involved in CO2 fixation (Rubisco, Rubisco activase (RA), Rubisco binding protein (RBP)), NH4+ assimilation (glutamine synthetase (GS) and glutamate synthase (GOGAT)), using immunoblotting, and in the antioxidative defense as a result of Cu or Mn excess in barley leaves (Hordeum vulgare L. cv. Obzor). Activities and isoenzyme patterns of superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and catalase (CAT), as well as the levels of ascorbate (ASC), non-protein sulfhydryl groups, hydrogen peroxide and oxidative damage to proteins were determined. Data were correlated to the accumulation of Cu or Mn in the leaves after 5 days supply of heavy metal (HM) excess in the nutrient solution. In the highest Cu excess (1500 muM), Rubisco LS and SS were reduced considerably whereas under the highest Mn concentrations (18,300 muM) only minor changes in Rubisco subunits were detected. The RBP was diminished under the highest concentrations of both Cu or Mn. The bands of RA changed differently comparing Cu and Mn toxicity. GS decreased and GOGAT was absent under the highest concentration of Cu. At Mn excess Fd-GOGAT diminished whereas GS was not apparently changed. The development of toxicity symptoms corresponded to an accumulation of Cu or Mn in the leaves and to a gradual increase in protein carbonylation, a lower SOD activity and elevated CAT and GPX activities. APX activity was diminished under Mn toxicity and was not changed under Cu excess. Generally, changes in the isoenzyme profiles were similar under both toxicities. An accumulation of H2O2 was observed only at Mn excess. Contrasting changes in the low-molecular antioxidants were detected when comparing both toxicities. Cu excess affected mainly the non-protein SH groups, while Mn influenced the ASC content. Oxidative stress under Cu or Mn toxicity was most probably the consequence of depletion in low-molecular antioxidants as a result of their involvement in detoxification processes and disbalance in antioxidative enzymes. The link between heavy metal accumulation in leaves, leading to different display of oxidative stress, and changes in individual chloroplast proteins is discussed in the article. (C) 2004 Elsevier B.V. All rights reserved.