title: [Energy-dependent uptake of phenazinemethosulfate in isolated chloroplasts].
abstract: The concentration and absorption of methylphenazinium cations (MP+) in suspensions of pea chloroplasts are simultaneously lowered during rapid (approximately 10s) illumination. The light-induced changes of absorption and concentration of MP+ reveal similar sensitivity towards some inhibitors and uncouplers and are determined by MP+ uptake by the thylakoids. The time-course of light-induced MP+ uptake was found to be modified in the presence of dithioerythritol, Mg2+ and ATP, i. e. under conditions which induce the ATPase activity and ATP hydrolysis in chloroplasts. The kinetic curve of light-induced MP+ uptake under these conditions consists of a relatively fast (approximatley 10 s) and a slow (approximately 10 min) components. The slow ATP-dependent component of MP+ uptake is enhanced by low concentrations of gramicidin and is completely inhibited by the energy transfer inhibitor--dicyclohexylcarbodiimide. The data obtained suggest that the light-induced energization of the chloroplast membrane is accompanied by the transport of MP+ into the thylakoids against the electrical potential and concentration gradients.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001693:Biological Transport, Active; D002736:Chloroplasts / Q000378:metabolism*; D007700:Kinetics; D008027:Light; D008773:Methylphenazonium Methosulfate / Q000378:metabolism*; D010619:Phenazines / Q000378:metabolism*; D010944:Plants / Q000378:metabolism
chemical_list: D010619:Phenazines; D008773:Methylphenazonium Methosulfate; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases
vernacular_title: Energozavisimoe pogloshchenie fenazinmetosul'fata v izolirovannykh khloroplastakh.