title: The effect of deoxycholate-treatment to the photoreactions of the active pigments in photosynthesis.
abstract: In the heavy fraction of deoxycholate-treated spinach chloroplasts the chlorophyll aII activity is high and the chlorophyll aI activity is low when no artificial electron donor is added. The addition of the photosystem I donor system N-methyl-phenazonium sulphate plus sodium ascorbate (PMS + Asc) leads to a complete reactivation of the chlorophyll aI reaction. The addition of the photosystem II donor system p-benzohydroquinone plus sodium ascorbate (HQ + Asc) leads to an inhibition of the chlorophyll aII activity. From these results we conclude: 1. Besides an interruption of the linear electron flow between the two photosystems deoycholate-treatment leads to a block of the electron flow from water to photosystem II. 2. In deoxycholate-treated chloroplasts the linear electron flow in photosystem II just like in Tris-washed, heat-treated or aged chloroplasts, is replaced by a cyclic one.
mesh_terms: D001205:Ascorbic Acid; D001594:Benzyl Viologen / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism*; D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism*; D003840:Deoxycholic Acid / Q000494:pharmacology*; D004237:Diuron / Q000494:pharmacology; D004579:Electron Transport / Q000187:drug effects; D006873:Hydroquinones; D008773:Methylphenazonium Methosulfate; D010788:Photosynthesis / Q000187:drug effects*; D010944:Plants / Q000378:metabolism; D013775:Tetraphenylborate / Q000494:pharmacology
chemical_list: D006873:Hydroquinones; D003840:Deoxycholic Acid; D001594:Benzyl Viologen; D002734:Chlorophyll; D008773:Methylphenazonium Methosulfate; D013775:Tetraphenylborate; D004237:Diuron; D001205:Ascorbic Acid