CHAPTER XIV 

 SPECIFIC FERMENTS OF THE CANCER CELL 1 



THE chief distinction between a living protein and any 

 more or less complex chemical group or dead cell is that 

 the living protein contains within itself different ferments 

 or enzymes. Many of these ferments are common to several 

 different forms of living protein or at least bear a close 

 resemblance to each other, but it is also probable that each 

 and every form of living cell contains within itself a specific 

 enzyme which is distinctive for that given form of protein, 

 and is present in no other. 



While as yet ferments have not been isolated in a chemic- 

 ally pure state, and we have not an exact knowledge of 

 their chemical nature, yet they are commonly regarded as 

 albuminous, and their functions are specific and fairly 

 well known. This at least is true of the soluble ferments 

 such as the amylases, proteoses, and lipases. Again, there 

 are examples of ferments of similar or nearly like consti- 

 tution which are formed by more than one variety of cell 

 (thus ptyalin formed by the salivary glands and diastase 

 formed by the pancreas are both starch-splitting ferments). 



The above examples are all of ferments which are water 

 soluble, and which are active outside of the cell that pro- 

 duces them. They are ferments which are excreted by the 

 cell and are used by the more highly developed forms of 

 animal life for the purpose of converting complex chemical 

 bodies into more simple forms, so that they may be of 

 service to the whole, through their reaction with other 

 ferments contained in other body cells. 



1 This chapter is contributed by J. Walter Vaughan and the work has 

 been done by the aid of the Chase Cancer Fund in the research laboratory 

 of Harper Hospital, Detroit, Michigan 



