The Role of Ascorbate Free Radical as an Electron Acceptor to Cytochrome b-Mediated Trans-Plasma Membrane Electron Transport in Higher Plants.
نویسندگان
چکیده
The action of ascorbate free radical as an electron acceptor to cytochrome b-mediated trans-plasma membrane electron transport is demonstrated. Addition of ascorbate free radical to ascorbate-loaded plasma membrane vesicles caused a rapid oxidation of the cytochrome, followed by a slower re-reduction. The fully reduced dehydroascorbate was ineffective.
منابع مشابه
The Role of Ascorbate Free Radical as an Electron Acceptor to Cytochrome 6-Mediated Trans-Plasma Membrane Electron Transport in Higher Plants'
In highly purified plasma membrane fractions of at least six higher plant species, a specific high-potential b-type Cyt (redox potential at pH 7.0 between +120 and +160 mV, a band at 560-561 nm) has been detected (Asard et al., 1989; Askerlund et al., 1989). This component is reducible in vitro by sodium ascorbic acid and constitutes 60 to 80% of the total Cyt amount detectable in plant plasma ...
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ورودعنوان ژورنال:
- Plant physiology
دوره 104 4 شماره
صفحات -
تاریخ انتشار 1994