Interaction of Viologen Dyes with Chromatophores and Reaction-center Preparations from Rhodospirillum Rubrum
نویسندگان
چکیده
Various low-potential viologen dyes enhance light-induced absorption changes in the nearinfrared region (t.A870) in chromatophore preparations from Rhodospirillum rubrum in the presence of dichlorophenol indophenol and a high concentration of ascorbate (DCPIP + asc). An increase in t.A870 was also observed in large reaction-center preparations from R. rubrum with viologens in the presence of ascorbate. Our results indicate that E~of the primary electron acceptor X may be as low as 0·37 V, as .suggested recently by P. A. Loach (1973, personal communication) .
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