ELECTRON TRANSPORT IN R. RUBRUM 



297 



^6 



d 5 



Q 

 liJ 



cr 

 o 

 ij- 



Q- 

 < 



- 2 



e 



^ 



(PiL 6.7mM 

 (ASCORBATE) . 2.5 mM 



AT TIME 



10 15 20 

 TIME (MIN.) 



25 30 35 



Fig 17 Effect of oxidant and reductant on steady state photophos- 

 phorylation of "bound ADP" with R. rnbrum chromatophores. Experi- 

 mental conditions were the same as for Fig. 16 with exceptions as 

 follows: R. nibnim chromatophores (G), washed three tmies; ADP, 

 not added; reactions were started in the presence of 2.5 mM ascor- 

 bate in light, :md after 15 minutes 0.10 ml. of water, 0.01 M fern- 

 cyanide or 1.0 M ascorbate was added, then reactions were further 

 carried out in continuous "light on" or in "light off." Half-closed and 

 solid symbols represent reactions in light-off and incontmuous dark- 

 ness, respectively (74). 



