CHEMILUMINESCENCE OF CHLOROPHYLL in vitrO 49 



be shifted perhaps 10 to 15 m^ toward the blue, and that would fit with this shift 

 observed here in the absorption spectrum changes, but I think better measure- 

 ments have to be made before one can say anj-thing conclusive about it. 



Gaffron: The importance of these observations is not only that they permit 

 an evaluation of the reactions of chloroplasts but that they demonstrate how 

 aggregates of chlorophyll seem to be particularly apt to bind substances which, 

 when they react chemically, may cause chemiluminescence. An oxidation appar- 

 ently must occur right at the chlorophyll. 



Strehler: I should point out that dried chloroplasts treated with ethanol and 

 chloroplasts treated with aldehyde and base do not show this luminescence. You 

 have to remove the chlorophj-ll from its bound form, I believe, in order to obtain 

 this chemiluminescence. 



Gaffron: That would be understandable. In chloroplasts so many other sub- 

 stances which can't be easily oxidized stick to chlorophyll. 



Frenkel: What has happened to your efforts to find coenzymes? Is there any 

 chance that you can modify your procedure and use this method for picking up 

 coenzymes? Do you think you can now eliminate that? 



Strehler: Yes, I think it can be eliminated. It is a relatively sensitive method, 

 but not as good as fireflies for ATP, and we hope to return to these experiments 

 some time, if somebody does not do them in the meantime. 



References 



1. Strehler, B. L., and Arnold, W. A., J. Gen. Physiol., 34, 809 (1951). 



2. Arthur, W. E., and Strehler, B. L., Arch. Biochem. and Biophys., 1957, in press. 



3. Vishniac, W., and Ochoa, S., /. Biol. Chem., 195, 75 (1952). 



4. Strehler, B. L., and Cormier, M. J., Arch. Biochem. and Biophys., ^7, 16 



(1953). 



5. Strehler, B. L., and Cormier, M. J., /. Biol. Chem., 211, 213 (1954). 



(■>. Fischer, H., and Stern, A., in Fischer and Orth's Chemie des Pyrrols, Vol. 2, 

 Akadem. Verlagsgesellschaft, Leipzig, 1940. 



