[Effect of deuteration on the gramicidin-sensitive electron-transport reactions in chloroplasts].
The uncoupling effects of gramicidine and NH4Cl on the light-induced electron transport were studied in isolated pea chloroplasts placed in H2O- or D2O-media. Gramicidine at 10(-6) M had no uncoupling effect on the rate of ferricyanide-supported O2 evolution in a D2O-medium, but enhanced the ferricyanide reduction in a H2O-medium and completely inhibited the light-induced alkalinization both in H2O- and D2O-suspended chloroplasts. The rate of electron transport with methylviologen as an acceptor was gramicidine-sensitive (uncoupling) both in preparations with H2O and D2O. In D2O-suspended chloroplasts the phosphorylation activity was retained as well as control of ferricyanide-dependent electron flow by ADP--phosphate and NH4Cl. It was assumed that some electron carriers on the inner surface of thylakoid membranes become inaccessible to ferricyanide upon deuteration.
D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism*; D003903:Deuterium / Q000494:pharmacology*; D017666:Deuterium Oxide; D004579:Electron Transport / Q000187:drug effects; D006096:Gramicidin / Q000494:pharmacology*; D007700:Kinetics; D008027:Light; D010944:Plants / Q000378:metabolism; D014867:Water / Q000494:pharmacology*
D014867:Water; D006096:Gramicidin; D003903:Deuterium; D017666:Deuterium Oxide
Vliianie deĭterirovaniia na chuvstvitel'nost' élektronotransportnykh reaktsiĭ v khloroplastakh k deĭstviiu gramitsidina.