Fluorescence induction in intact spinach chloroplasts.

R C Jennings; G Forti

doi:10.1016/0005-2728(75)90189-9

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Fluorescence induction in intact spinach chloroplasts.

R C Jennings·G Forti

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Abstract

Under conditions in which the Photosystem II quencher is rapidly reduced upon illumination, either after a preillumination or following treatment with dithionite, the fluorescence-induction curve of intact spinich chloroplasts (class I type) displays a pronounced dip. This dip is probably identical with that observed after prolonged anaerobic incubation of whole algal cells ("I-D dip"). It is inhibited by 3(3,4-dichlorophenyl)-1,1-dimethylurea and occurs in the presence of dithionite, sufficient to reduce the plastoquinone pool. It is influenced by far red light, methylviologen, anaerobiosis and uncouplers in a manner consistent with the interpretation that it represents a photochemical quenching of fluorescence by an electron transport component situated between the Photosystem II quencher and plastoquinone. Glutaraldehyde inhibition may indicate that protein structural changes are involved.

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Anaerobiosis Chloroplasts Darkness Dithionite Diuron Electron Transport Glutaral Kinetics Light Paraquat Photophosphorylation Plants Quinones Spectrometry, Fluorescence Time Factors Uncoupling Agents Journal Article

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R C Jennings, G Forti. 1975-07-08. Fluorescence induction in intact spinach chloroplasts.. https://doi.org/10.1016/0005-2728(75)90189-9

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