152 



WALTER JONES 



the nucleic acid of the gland extract, but only one of them is subsequently 

 deaminized. This necessitates the conclusion that both thymus and pan- 

 creas contain two independent deaminizing ferments (guanase and ade 

 nase), only one of which (adenase) is present in the spleen. 



An equally curious result was obtained with pig's liver. The ei 

 products of self-digestion are guaninc and xanthine. This is easily ac- 

 counted for by assuming that the guanine set free from the nucleic acic 

 remains unchanged, but that the adenine is deaminized to hypoxanthine 

 which in turn is oxidized to xanthine. 



Representing the purine ring with its three replaceable hydrogen atoi 



/H 

 by the symbol P H, the results of autodigestion may be expressed as fol- 



\ H 

 lows : 



/KH 2 

 P OH 

 \H 



guanine 



P 

 \H 



adenine 



/NH 2 

 P OH 

 \H 



guanine 



P 

 \H 



adenine 



/H /H 



P OH P OH P OH 



\H \H \ H 



xanthine hypoxanthine hypoxanthine 



Pig' 8 Thymus and Pancreas Pig's Spleen 



(Jones and Austrian (a), 1906) (Jones and Winternitz, 1905). 



/OH 

 P OH 



Uric Ac-id 



P OH 

 \H 



guanine 



/OH 

 P OH < 

 \ H 



xanthine 



Pig's Liver 

 (Jones and Wintemitz, 1905) 



P NH 

 \H 



adenine 



P OH 

 \ H 



hypoxanthine 



