PHOTOOXIDATION AND PHOTOREDUCTION REACTIONS 265 



idea that one electron transport chain functions in both areas, with the 

 oxidative chain involving those components from NAD through RHP. 

 Although Geller favors separate electron pathways for the photochem- 

 ical and oxidative metabolism (35), his data on the effect of inhibitors 

 correlate very nicely with the scheme proposed above. Thus, oxida- 

 tive phosphorylation was not affected by antimycin A or HQNO, whereas 

 photophosphorylation was strongly inhibited. Furthermore, amytal 

 strongly inhibited NADH oxidation aerobically, but did not affect the 

 photophosphorylation process. 



ACKNOWLEDGMENTS 



The author wishes to acknowledge the very capable technical assistance of 

 Mrs. Ann Tirpack and Miss Dorothy Limbach in the course of the investigations 

 reported above. 



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