BERNARD L. STREHLER 



205 



mounted just below the beam of ionizing electrons of the mass spec- 

 trograph. Molecules or fragments thereof, volatilized by heating in 

 vacuo (within the mass spectrometer) were analyzed both for their 

 mass and the frequency of their occurrence. Riboflavin was run as a 

 model compound and, through analysis of the "mass cracking pat- 

 tern" of this compound, it was possible to show that the parent com- 

 pound was successively broken down into smaller pieces in a manner 

 deducible from its structure. 



Fig. 8. Mass cracking pattern of firefly luciferin II. The compound used in the 

 mass spectrographic degradation is luciferin II, a compound arising from 

 luciferin through gentle oxidation with O2 under acid conditions. It bears 

 a strong resemblance to luciferin in physical properties, but has no enzy- 

 matic activity. 



Figures 6, 7, and 8 show respectively the mass cracking pattern of 

 riboflavin, the structures of the pieces derived from riboflavin pyroly- 

 sis, and the mass cracking pattern of luciferin. 



In an attempt to untangle the data at hand on the masses arising 

 from luciferin, the mass 234, which seems to be a core of the main 

 molecule, was broken down into all combinations of C,0,H,N, and S 

 which can give mass 234. Some of these combinations are impossible 

 by reason of valence considerations, others are impossible on the basis 



