620 



LIGHT AND LIFE 



TABLE 3 

 Mehler Reaction and Oxidative Photophosphorylation 



Reaction 

 Mixture 



/xmoles O2 

 consumed 



^tmoles 



acetaldehyde 



produced 



^moles Pi 

 esterified 



complete 

 minus dye 

 minus ethanoi 

 minus light 



0.7 

 0.6 

 

 



0.67 

 0.62 

 

 



3.8 

 0.0 

 3.8 

 



that no phosphorylation occurs. The reduced dye may reduce the 

 photochemically generated oxidant and, in so doing, permit the flow 

 of electrons from the photochemical reductant through a phosphory- 

 lation step to oxygen. It is suggested that the product of this oxygen 

 reduction is water, inasmuch as hydrogen peroxide production does 

 not appear to be related to the indophenol-catalyzed reactions. 



XH 



-^dyeH2 — *YOH 



O2, 



->0c 



^^ H2O 



Fig. 4. Oxidative pliotosynthetic pliosphorylation. 



REFERENCES 



1. Brown, A. H., Nier, A. O. C, and Van Xonnan, R. W .. Pluul Physiol.. 27 

 320-333 (1952). 



2. Brown, A. H., and VVcis, D., Plaiil Physiol.. M. 224-234 (H).")')). 



3. DcLuca, C, Weber, M. M., and Kaplan, N. O.. ]. liiol. Chriii.. 223, .'.r)9-:»67 



(1956). 



4. Kcilin, D., and Hartrce, K. I-., liiorhcin. /.. 39. 293-301 (1945). 



5. Krogmann, D. \V., and Vennesland, B., ./. liiol. Chcm., 234, 2205-2210 (1959). 

 fi. Mehler, A. H., Arch. Biochem. and liiophys., 33, 65-77 (1951). 



7. Racker, F,., Methods in Knzyniology (Colowick. S. P.. and Kaplan. \. O., cds.), 

 Vol. Ill, p. 293, Academic Press! New York (1957). 



