202 Nutrition and Tannase Production 



has stated concerning my work that the formation of the enzyme tannase 

 is an exception to the general rule. The work of other investigators previ- 

 ously mentioned has indicated, however, that the production of certain 

 enzymes in other organisms is governed entirely by the character of the 

 nutrition. 



Dox'* has considered only the influence of external environment upon the 

 formation of the enzymes. It is to be expected that protease, lipase, nuc- 

 lease, inulase and perhaps some of the other enzymes would be produced 

 . because the substances which they transform are present in the mycelium. 

 If the action of an enzyme is reversible and they are synthesizing agents, 

 then the question arises: "can the products of the decomposition induce 

 the formation of enzyme?" In my experiments the only substance besides 

 tannic acid capable of inducing the formation of the tannase is gallic acid, 

 which is a decomposition product of tannic acid. 



Might it be possible that all of the enzymes are produced only in response 

 to the influence of the zymolyte or to the products of its decomposition 

 present either in the nutrient solution or in the mycelium? There is a con- 

 siderable amount of evidence indicating that one or the other is always pres- 

 ent, but there is also evidence that certain enzymes are seemingly produced 

 in the entire absence of the zymolyte or the products of its decomposition. 

 The whole problem is a complex one and requires investigation. 



8s Enzyme Studies of Lower Fungi, loc. cit. 



