260 ELECTRON TRANSPORT 



PROBABLE REACTION SITES 

 in R. rubrum 



Light 



CytO. C2 ^ — DPIPHa. TMPD, 

 A Cyfo. c, MBHj 



CytO. b 



t 



RHP ► 02 



t 



Ubiquinone 



/ 



Production 

 e- * *^^ 



Ferredoxin-*'Flavo- - ^i 



Protein 

 , (FMN), 



02, Methyl Red, 

 Tetrazolium Blue, S04 = 

 Disulfide {With Viologen Dyes) 



Succinate 

 "* Fumorate 



Fig. 17. Reaction sites for photochemical reactions 

 observed with R. rubrum chromatophores. 



INHIBITION SITES 

 in R. rubrum 



Succinate 

 "*■ Fumorate 



(FMN) ' 



^■^ -Qu(nacri 



Fig. 18. Sites of inhibitor action with R. rubrum 

 chromatophores. 



The components contained within the R. nibnim chromatophores 

 are presented in Fig. 16 in a logical sequence. There is ample evidence 

 that cytochrome C9 contained in this organism is photooxidized in a 

 primary photochemical reaction by the BChl (9-13,28). This organism 

 also contains a compound whichappears to be similar to the ferredoxin 

 isolated by Tagawa and Arnon from Chro)uatium (47), Preliminary 

 evidence indicates that the ferredoxin is tightly bound to the chroma- 

 tophore in the case oiR. riibrn nt andis not readily extracted. The first 

 compound shown to be reducedby the action of light in the case of plant 



