THE URIC ACID FERMENTS. 
ELBEET W. EOCKWOOD. 
Within a few years our knowledge of the formation and destruction of uric 
acid in the body has been much broadened. For a long time after its isolation 
its origin, significance, place of formation and the agents active in its produc- 
tion and decomposition were unknown. In these respects the facts differ much 
in the cases of birds and mammals and only the cases of mammals will be here 
considered. 
At the present time it is the belief of physiologists that uric acid is largely 
formed in the liver through the action of ferments upon the nucleins. A 
synthetic formation of uric acid in the body may take place, but convincing 
proof of this is wanting. The nucleins which furnish much of the material for 
uric acid belong to the conjugate proteins. They contain 5 per cent or more 
of phosphorus and, in addition to a simple protein, the purin ring, 
N-C 
I I 
C C— N\ 
I c 
N— C— N/ 
found likewise in uric acid, 
HN-CO 
1 I H, 
OC C- N \ 
I II CO 
HN— C— NH/ 
The relationship of the purin bodies to uric acid may be seen from the 
-following: 
C0H4N4 Purin 
C6H3N4NH2 Amino-purin (Adenin) 
C5H3N4NH2O Amino-oxypurin (Guanin) 
G5H4N4O Oxypurin (Hypoxanthin) 
C5H4N4O2 Dioxypurin (Xanthin) 
• CfH 4 N 403 Trioxy purin (Uric Acid) 
From the liver have been extracted ferments which will destroy nucleins and 
will oxidize hypoxanthin and xanthin to uric acid. The uric acid thus formed 
is referred to as of two varieties, the endogenous — that derived from the nucleins 
of the tissues — and the exogenous — that coming directly from the nucleins of the 
foods. Of the uric acid which is produced in this manner a considerable part, 
varying in different animals, appears to be destroyed before elimination, so that 
the uric acid found in the urine represents merely the difference between the 
amounts produced and destroyed. This decomposition appears to be, at least in 
part, due to a ferment, the uricolytic. 
This paper may be regarded as a report on some uncompleted work which 
is being carried on in our laboratory. Its purpose it to throw more light upon 
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