Is the Quinol oxidoreductase a b/Rieske-type one in photosynthetic green sulfur bacteria?

First of all，we searched cytochrome c1-like protein in green sulfur bacteria.After solubilization of membranes and the subsequent ion-exchange chromatography and SDS-PAGE analysis combined with heme staining，we got crude fraction containing cytochrome c1-like protein.However，its N-terminal amino acid might be blocked。We need a different strategy in the future，that is now under consideration.Secondly，we studied the electron transfer pathway in heliobacteria。Heliobacteria are gram positive bacteria，whose reaction center(RC)is classified as a type 1.However，it has been unclear whether the RC contains membrane-bound cytochrome c(Cyt C)which donates electrons to P798as well as F I D2A文件D2/F I D2B文件D2 protein on the acceptor side。We analyzed the reaction mechanism on the donor side with intact cells and membranes of Heliobacterium gestii.P798 I D 1 I D 1，immediately formed after flash excitation，was rereduced in two phases with t I D 21/2 I D 2=3 and 7 ms，respectively.The fast phase was attributable to the electron transfer from cyt c to P798，and the slow one was considered as the back reaction。Since the reaction rate from cyt c to P798was much faster in the case of in vivo(t i D21/2 ii D2=100µs)，we have studied the effect of ion strength and/or temperature.

First of all, we searched cytochrome c1-like protein in green sulfur bacteria. After solubilization of membranes and the subsequent ion-exchange chromatography and SDS-PAGE analysis combined with heme staining, we got crude fraction containing cytochrome c1-like protein. However, its N-terminal amino acid might be blocked. We need a different strategy in the future, that is now under consideration.Secondly, we studied the electron transfer pathway in heliobacteria. Heliobacteria are gram positive bacteria, whose reaction center (RC) is classified as a type 1. However, it has been unclear whether the RC contains membrane-bound cytochrome c (cyt c) which donates electrons to P798 as well as FィイD2AィエD2/FィイD2BィエD2 protein on the acceptor side. we analyzed the reaction mechanism on the donor side with intact cells and membranes of Heliobacterium gestii. P798ィイD1+ィエD1, immediately formed after flash excitation, was rereduced in two phases with tィイD21/2ィエD2=3 and 7 ms, respectively. The fast phase was attributable to the electron transfer from cyt c to P798, and the slow one was considered as the back reaction. Since the reaction rate from cyt c to P798 was much faster in the case of in vivo (tィイD21/2ィエD2=100μs), we have studied the effect of ion strength and/or temperature.