604 



Jagendorf and Hind 



cofactors. Although we are occasionally tempted to 

 speculate from this on the existence of two 

 phosphorylation sites with pyocyanine and only one with 

 FMN, etc«, in the absence of further evidence this 

 conclusion is questionable. 



30 



60 90 120 150 180 



SECONDS 



Figure 2, formation and decay of X with various 

 cofactors. 



Solid lines: ATP recovered as function of 

 illumination time at pH 6 and 5 C, in white light of 

 8600 ft. candles. Dashed lines: ATP recovery after 

 turning off light at arrow and giving increasing dark 

 interval before injection into phosphorylating reagents 

 at pH 8.0, Ferricyanide 3*0 mM. Pyocyanine and methyl 

 viologen, 50 uM. 



Both the formation of X in the light , and its 

 decay in the dark show apparent first order reaction 

 kinetics. The meaning of the formation rate constants 

 seems ambiguous, due to lack of information as to the 

 existence of simultaneous decay processes, or of the 

 total concentration of the reacting species. The kinetic 





