/. ]VOOl)LAi\D HASTINGS AND I KRNON C. BODE 305 



dependent, and protection against the destruction may be obtained 

 by adding scrum albumin to bind the hicifcrin. 



The albumin effect suggests that enzymatic and nonenzymatic oxi- 

 dations may be similar, and that the major difference may lie in the 

 participation of the protein, one of whose functions might be to trap 

 and conserve the energy from the reaction. The reversibility of the 

 nonenzymatically oxidized luciferin may be from an intermediate. 



.A (NO ADDITIONS) 

 • ^ • • 



y^ B ^ [lM (NH2)2S04 * AL*bUMIN] 



-•-. 



C pM (NH^)2SO^] 



D [2M (NHJ SOJ 



TIME - MINUTES 



Fig. 9. This figure illustrates the nonenzymatic loss of luciferin luider several 

 conditions. Added salt increases the rate of the loss of luciferin activity, and 

 albumin protects against this loss. The solutions were incubated at 22°C in a 

 water bath, and aliquots were removed at the times indicated and assayed for 

 luciferin. The />H of all incubation mixtures was adjusted to 7.4. 



A final consideration relates to the possibility that salt has an 

 effect upon the quantum yield of the reaction. Any effect which de- 

 creases the energy losses via competitive radiationless pathways should 

 increase the lifetime of the excited state, and therefore the quantum 

 yield. 



In the case of bioluminescence, a quantum yield increase might 

 result from an altered or more effective combination of luciferin 

 with the luciferase. In fact, the role of albuinin might be related 

 to a quantum yield effect. To test these questions experimentally it 

 will be of importance to learn more concerning the nature of the 

 excited complex which emits. In particular, it will be important to 



