CLEAVAGE OF PYROMUCURIC ACID BY MOLD 



ENZYMES 



ARTHUR W. DOX and RAY E. NEIDIG 

 (Chemical Section of the Iowa State College, Arnes, Iowa) 



In a recent paper^ we have presented data showing that the 

 formol-titrimetric method of Sörensen can be applied to the de- 

 termination of the cleavage of hippuric acid by enzymes. The six 

 saprophytic fungi studied were found to produce an enzyme capable 

 of hydrolyzing as miich as 90 to 100 per cent. of a Solution of 

 sodium hippurate in the presence of toluene as an antiseptic. The 

 production of enzyme was independent of the presence of the cor- 

 responding Substrate in the nutrient medium upon which the fungus 

 was cultivated, and the age of the culture, within the limits studied, 

 had little influenae upon this enzymic activity. 



If we assume that the synthesis in the animal organism of hip- 

 puric acid from benzoic acid is an enzymic process, the synthesis of 

 the corresponding derivatives from substituted benzoic acids might 

 well be attributed to the same cause. It is known, for example, 

 that o-brombenzoic, salicylic, toluic and other substituted benzoic 

 acids, when administered orally, are conjugated with glycocoll and 

 excreted through the kidneys as o-brombenzoylglycocoU, salicyluric, 

 toluric, etc., acids. Likewise, a homologue of benzoic acid, e. g., 

 phenylacetic, may be conjugated in the same way and eliminated 

 as phenylaceturic acid. It is quite unlikely that these substituted 

 benzoic acids all require separate enzymes for their conjugation 

 with glycocoll, and it is equally improbable that the hydrolysis of 

 the substituted hippuric acids would require specific enzymes. 



This reasoning may be extended, also, to analogous Compounds 

 where the benzene nucleus is replaced by a heterocycle. For 

 example, ct-pyridine carboxylic acid is united in exactly the same 

 manner with glycocoll and excreted as a-pyridinuric acid. The 



* Dox and Neidig : Zeitschr. f. physiol. Chem., 1913, Ixxxv, p. 68. 



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