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Hidehiro Sakurai, Studies on photophosphorylation II. Uncoupling of chloroplasts by anions at low temperatures and at acidic pH values, Plant and Cell Physiology, Volume 13, Issue 5, October 1972, Pages 857–866, https://doi.org/10.1093/oxfordjournals.pcp.a074797
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Abstract
Photophosphorylation of spinach chloroplasts was uncoupled by preincubation at 0°C in the presence of a neutral salt at pH 6.0 to 6.5 (“cold-anion uncoupling”). Preincubation at 20°C caused some depression in both photophosphorylation and the Hill reaction, but the efficiency of photophosphorylation was not depressed much. Low pH values accelerated uncoupling. The effectiveness of anions tested as sodium salts in inducing uncoupling was of the order: SCN->>NO3−>Cl−>SO42− There was little difference in effectiveness among monovalent cations; LiCl, NaCl, KCl, RbCl and CsCl. 10−4m ATP or ADP largely protected chloroplasts from cold-anion uncoupling. Addition of EDTA-extract or dicyclohexylcarbodiimide to uncoupled chloroplasts partially restored photophosphorylation. These observations suggest that inactivation of chloroplast ATPase is one cause of cold-anion uncoupling.
At low light intensities, the time lag and the depression of the efficiency of photophosphorylation were more pronounced in cold-anion uncoupled chloroplasts than in the control chloroplasts.
