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Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses
Published on: August 9, 2019
Inhibition of Photosystem II in Isolated Chloroplasts by Lead
C D Miles1, J R Brandle, D J Daniel
1Division of Biological Sciences, University of Missouri, Columbia, Missouri 65201.
Abstract:
Inhibition of photosynthetic electron transport in isolated chloroplasts by lead salts has been demonstrated. Photosystem I activity, as measured by electron transfer from dichlorophenol indophenol to methylviologen, was not reduced by such treatment. However, photosystem II was inhibited by lead salts when electron flow was measured from water to methylviologen and Hill reaction or by chlorophyll fluorescence. Fluorescence induction curves indicated the primary site of inhibition was on the oxidizing side of photosystem II. That this site was between the primary electron donor of photosystem II and the site of water oxidation could be demonstrated by hydroxylamine restoration of normal fluorescence following lead inhibition.
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