Tocopherol is the scavenger of singlet oxygen produced by the triplet states of chlorophyll in the PSII reaction centre.
نویسندگان
چکیده
Recent developments on the role of tocopherol in the antioxidant network of the chloroplast and, in particular, in the protection of PSII in high light are summarized. The origin and conditions for singlet oxygen production in the reaction centre via P680 triplet formation are discussed, as well as the scavenging of this singlet oxygen by tocopherol. This is probably the obligatory function of tocopherol in the plant in high light acclimation. Furthermore, tocopherol is part of the modulation system of ROS in stress signalling.
منابع مشابه
Singlet oxygen production in photosynthesis.
A photosynthetic organism is subjected to photo-oxidative stress when more light energy is absorbed than is used in photosynthesis. In the light, highly reactive singlet oxygen can be produced via triplet chlorophyll formation in the reaction centre of photosystem II and in the antenna system. In the antenna, triplet chlorophyll is produced directly by excited singlet chlorophyll, while in the ...
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ورودعنوان ژورنال:
- Journal of experimental botany
دوره 57 8 شماره
صفحات -
تاریخ انتشار 2006