1889-90.] Dr G. E. C. Wood on Enzyme Action. 29 
Einkler and Miller bacilli continued to act in distinctly acid solu- 
tions. But the two enzymes which each of these organisms possess 
seemed not to be equally affected by the acidity. The precipitation 
of the casein occurred in reactions where the peptonisation was 
apparently completely inhibited. We must therefore conclude 
that the enzymes of these organisms are, in each case, distinct, and 
that the enzymes, even in the same organism, are not alike as 
regards their capacity of acting under different conditions. 
Gelatine and blood serum cultures of the four organisms were 
found, in no case, to exert any diastatic action on starch. A medium 
containing starch was then inoculated with cholera bacillus, which 
after being allowed to grow for some time was sterilised at 60° C. 
The amount of sugar present was then estimated in a small quantity. 
By means of a pipette, 25 c.c. of the sterilised culture was then intro- 
duced into a starch solution, and incubated for six days, when the 
amount of sugar was again titrated. The quantity found was not, 
however, greater than what had been introduced with the sterilised 
culture fluid, so that no evidence of ferment action was exhibited. 
Although the experiment was repeated twice, a negative result had, 
on both occasions, to be recorded. It is possible that the ferment 
may have been destroyed, or that some condition was present which 
prevented its action. It appears to me more probable, however, 
that the power of converting the starch into sugar may here exist 
only in the protoplasm, it not having yet become developed into an 
enzyme separable from the organism. It is not necessary to consider 
the primary processes of digestion as dependent on soluble ferments. 
The enzyme function should, as Hueppe * has insisted, be regarded 
as a secondarily derived function of the protoplasm. The process of 
digestion, as observed in its simplest form, is an intracellular diges- 
tion, and is not, as Krukenbergf has conclusively shown, dependent 
on enzymes, but is inherent in the protoplasm itself. The enzymes 
are merely further differentiations of this primitive power of the 
protoplasm in the same way as muscle and nerve are to be regarded 
as represented in the contractility and irritability of a structureless 
mass of undifferentiated protoplasm. We are accordingly prepared 
* Die Methoden der BaJcterien-Forschung, 1888; “Abschnitte ueber Biologie,” 
Die Hygienische Beurtheilung des Trinkivasser, 1887. 
t Vergleichend-physiologische Vortrdge, Heidelberg. 
