J. WOODLAND HASTINGS AND VERNON C. BODE 299 



LH^— ALB + ^Oa 

 \ 



LUCIFERASE \^ 

 ■»- L 



Lqx + HEAT 



SALT) 

 ^Ge^;?^ L,NT (SALT) 



(SALT) ^ Lox-^hV 



i-ox 



Fior. I. This figure illustrates the proposed pathways for the I)rcakclown of 

 liuiferin. Ihe reduced starting material, or luciferin, is designated as LH.. Its 

 oxidation may proceed via a nonenzymatic pathway (bottom) which may be re- 

 versed by the use of reducing agents. This re%ersal is possible from an inter- 

 mediate (Li,,,) but not from the final product (L„j). Alternatively, the enzymatic 

 oxidation results in the production of an excited molecule, L*, which may decay 

 to the groiuid state either with the emission of light, or via a radiationless path- 

 way with the production of heat. L„^ is the oxidized luciferin. We have also repre- 

 sented the formation of an albumin-luciferin complex (top), which is less sensitive 

 to nonenzymatic oxidation, and niav presumably also he capable of enzymatic 

 oxidation. 



TABLE 2 

 The Effect of Salts Upon Luminescence 



Compound 

 Tris-maleate-NaOH, pU. 6.5 



Final Molar 



Concentration 



.12 



Relative Intensity 

 15" 



* Tris-maleate buffer was present in all assays except two, as noted. A stimulation 

 of light intensity can be ascribed to added salt, therefore, only when the relative 

 intensity is greater than the value of 15 which is attributable to the buffer. 



