Site-specific inhibition of photophosphorylation in isolated spinach chloroplasts by HgCl 2. II. Evidence for three sites of energy conservation associated with non-cyclic electron transport

Abstract

Energy transfer inhibition by HgCl 2 has been demonstrated to be selective for certain System I partial reactions. On the basis of different HgCl 2 effects on the System I reactions, reduced 2,6-dichlorophenolindophenol → methylviologen, diaminodurene → methylviologen and N-phenazine methosulfate cyclic, two sites of energy conservation associated with System I are proposed. Furthermore, these sites are in parallel with each other, in series with the site closely associated with Photosystem II and are shared between non-cyclic and cyclic electron transport.