F. I. TSUJI, A. M. CHASE AND E. N. HARVEY 



141 



0.8 



0.6 



0.0 



250 300 350 400 450 500 550 250 300 350 400 450 500 550 



WAVELENGTH IN m\A 



Fig. 3. Absorption spectra of 0.1 .V HCl solutions of doubly cycled luciferin, 

 purified further in \ arious ways as described in the text. In each set of spectra 

 the solid line represents the solution measured as soon as possible after being 

 prepared, with minimal exposure to air, whereas the other two curves were 

 measured after the solution had been exposed to air for the times indicated. 

 A, B, and C are from one luciferin preparation, and D and E from another. 

 It is apparent from inspection of these fi\e sets of absorption spectra (par- 

 ticularly C, D and E ) that tliey are similar in form and in the changes which 

 they undergo on exposure of the luciferin solutions to air. They may be 

 presumed to represent luciferin. See the text for further details. 



those of Fig. 3A represent a solution of luciferin isolated from the 

 same preparation by paper electrophoresis. 



Figure 3E shows the spectra of preparation II, washed with benzene 

 after the last step in Anderson's procedure, but not otherwise treated. 



