Dipartimento di Scienze Agrarie e Ambientali, Università degli Studi di Perugia, Perugia, Italy.
J Environ Sci Health B. 2011;46(8):715-22. doi: 10.1080/03601234.2011.594414.
To evidence a possible mechanism of defense toward oxidative stress induced by herbicides in plants, an investigation was carried on the activity of glutathione peroxidase (GPX) in Italian ryegrass (Lolium multiflorum) and in Festuca (Festuca arundinacea) in response to atrazine (6-chloro-N-ethyl-N'-isopropyl-1,3,5-triazine-2,4-diamine) and fluorodifen (4-nitrophenyl α,α,α-trifluoro-2-nitro-p-tolyl ether). In general, the herbicide treatments significantly induced GPX activity in the shoots of Italian ryegrass, whereas inhibited it in Festuca. These opposite behaviors are examined, taking into account the accumulation and persistence of the two herbicides in the plants, and they are discussed in terms of GPX counteraction to oxidative stress in the first case, and of a lower detoxification rate unable to prevent a deleterious effect on the GPX activity in the second case. Further information on the properties of Italian ryegrass and Festuca GPX were achieved by purification and isolation of the enzymes, performed by protein liquid chromatography and by electrophoretic analyses. GPX of both the plants were found to be heterodimer with multiple function in showing also glutathione S-transferase (GST) activity.
为了证明植物对除草剂诱导的氧化应激的可能防御机制，本研究调查了意大利黑麦草（Lolium multiflorum）和高羊茅（Festuca arundinacea）在受到莠去津（6-氯-N-乙基-N'-异丙基-1,3,5-三嗪-2,4-二胺）和氟草烟（4-硝基苯基α,α,α-三氟-2-硝基对甲苯醚）处理时谷胱甘肽过氧化物酶（GPX）的活性。一般来说，除草剂处理显著诱导了意大利黑麦草地上部的 GPX 活性，而抑制了高羊茅中的 GPX 活性。考虑到两种除草剂在植物中的积累和持久性，对这两种相反的行为进行了研究，并从 GPX 对第一种情况下氧化应激的拮抗作用和第二种情况下解毒速率较低导致对 GPX 活性产生有害影响的角度进行了讨论。通过蛋白质液相色谱和电泳分析，对酶进行了纯化和分离，进一步了解了意大利黑麦草和高羊茅 GPX 的特性。发现两种植物的 GPX 均为具有多种功能的杂二聚体，同时也显示出谷胱甘肽 S-转移酶（GST）活性。
