296 



ELECTRON TRANSPORT 



70 



60 



50 



i ^0 

 o 



< 30 



o 



E 



ADP EXTERNALLY ADDED 



(nryj moles) cq 



r 



20 



10 



20 



1 



NONE 



O o - 



5 10 15 



TIME (MIN.) 



20 



Fig. 16. Effect of externally added ADP on steady state of photo- 

 phosphorylation with R. rubrum chromatophores. Experimental 

 conditions were the same as for Fig. 12 with some exceptions as 

 follows: The chromatophores (G) were prepared by grinding of 

 cells with alkaline aluminum oxide and washing five times. Ascor- 

 bate, 4.5 mM; ADP, varied from to 60 m/^-moles as indicated. 

 Open and solid symbols show reactions in light and in darkness, 

 respectively. The dark reactions were carried out in the presence 

 of 60 m/i-moles of the ADP externally added (57). 



