The Rates of Photophosphorylation of the Blue-Green Alga Anacystis nidulans at Transition from Dark to Light. I. Rates under Conditions of Cyclic, Pseudo-Cyclic, and Non-Cyclic Electron Flow and in Presence and Absence of DCMU [3(3,4-Dichlorophenyl)-1,1-dimethylurea] and Desaspidin

Abstract

Summary The rates of ATP formation in Anacystis nidulans were calculated from the difference of the ATP level in dark and after one second illumination. The conditions used were N2, N2 + O2, and air + CO2 in combination with added inhibitors. One of them was DCMU [3(3,4-dichlorophenyl)-1,1-dknethylurea], an inhibitor of non-cyclic electron flow and the other one was desaspidin which inhibited specifically cyclic electron flow in the experiments described here. From the rates of ATP formation under the different conditions conclusions are drawn on the extent of the different types of photophosphorylation in vivo. The maximal rates obtained were about 270,µmoles ATP • mg chl−1 • h−1.