Hydrophobic "pocket" on photosynthesizing membrane near photosystem II

Studies concerning the effect of 2‐alkyl pyridine N‐oxides with different substituents on electron transfer, phosphorylation, and light‐dependent proton transport in photosynthesizing membranes of chloroplasts were conducted. It is determined that 2‐alkyl pyridine N‐oxides with short alkyl chains stimulate the Hill reaction and light‐dependent proton transport inside chloroplasts. Compounds having alkyl residues with 6‐10 carbon atoms in the chain inhibit electron transport, ADP phosphorylation, and reduction of ferrocyanide in thylakoids. A conclusion is drawn on the presence of the hydrophobic “pocket,” which is of importance for organization of the electron‐transport chain of chloroplasts, near photosystem II.