KINETICS OF THE BIOLUMINESCENT REACTION IN 



CYPRIDINA. I. 



By WILLIAM R. AMBERSON. 



(From the Physiological Laboratory, Princeton University, and the Laboratory of 

 Pure Science, Nela Research Laboratories , Cleveland, Ohio.) 



(Received for publication, March 21, 1922.) 



INTRODUCTION. 



Until the present time it has been proven impossible to isolate as 

 pure chemical individuals any of the reactants concerned in the 

 production of light by organisms. The work of Dubois^ and Harvey 

 has, however, indicated the general nature of such reactions as con- 

 sisting in the oxidation of a substrate, luciferin, catalyzed by 

 an enzyme, luciferase. Harvey^ believes that luciferin should be 

 placed among the natural proteoses on the borderland between the 

 proteoses and peptones, whereas luciferase is a protein probably 

 belonging to the albumin group. 



Quantitative studies upon such reactions are beset with several 

 difficulties, among the most important of which are (1) absolute 

 lack of information as to the concentration of the reactants present 

 in extracts, and (2) the rather highly labile character of the substrate, 

 luciferin, which readily oxidizes spontaneously without light produc- 

 tion in the absence of the enzyme. I have made an attempt, how- 

 ever, to discover something of the time relations involved in bio- 

 luminescent reactions, specifically to study the rate of decay of the 

 light produced when aqueous solutions of enzyme and substrate are 

 added together. This paper deals with a photographic method which 

 has been developed for this study, and with the results which it 

 indicates. 



* Dubois, R., La vie et la lumiere, Paris, 1914. 



* Harvey E. N., J. Gen. Physiol., 1919, i, 269. 



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