678 ARTHTJE ISAAC KENDALL 



It will be seen that bacteria grown on glucose agar contain nearly 

 twenty per cent less nitrogen, and materially more extractives than those 

 grown on media with the same nitrogenous constituents but without the 

 glucose. The significance of this difference is yet to be determined. 



Inasmuch as the immunizing processes are apparently inseparable from 

 nitrogenous substances, however, there may be some relationship between 

 a maximum nitrogen content of bacteria and their antigenic potency, 

 which may play a part in the large field of bacterial vaccines. In this 

 connection, the reciprocal variation of nitrogen and lipoids, clearly sug- 

 gested in the table, may also be of significance inasmuch as solubility 

 and anti-complementary properties of bacteria appear to be related to 

 the lipoidal content of bacterial bodies (Warden). Whatever the sig- 

 nificance of the composition of bacteria may be, it may be stated con- 

 fidently that the entire series of phenomena outlined above relating to 

 the sparing action of utilizable carbohydrates for protein in the energy 

 manifestations of bacteria and their effects upon the composition of bac- 

 teria even is of material importance in determining the nature and 

 extent of bacterial action. 



C. The Chemistry of Bacterial Metabolism 

 1. General Statements 



The chemistry of bacterial metabolism naturally is divided into two 

 rather distinct phases the anabolic, or structural, phase, which in point 

 of time occurs first, and the katabolic, or energy phase, which follows the 

 maturation of the bacterial cell. 9 The latter exceeds the former, both 

 with respect to the amount of material transformed and in respect to 

 the significance of the products resulting from the utilization of the 

 various substances for energy. 



Generally speaking, the structural or anabolic phase consists of a 

 series of hydrogenic condensations whereby simpler nitrogenous sub- 

 stances, as amino acids or polypeptids, are built into specific proteins; 

 where glycerin and fatty acids are synthesized to fats, and, in association 

 with phosphorus, into nucleins; and where glycogen-like bodies are ap- 

 parently synthesized from glucose. 10 This phase of bacterial development 



* It is almost certain that a certain amount of interchange referable to the anabolic 

 phase must take place throughout the period of vegetative activity of the cell. The 

 losses associated with the formation of enzymes and other essential excretions belong 

 in this group. 



10 Considerable evidence has accumulated indicating the possibility of a mutual 

 transformation of glycerin, alanin and glucose through pyruvic acid into the three 

 great types of proteins, carbohydrates, and fats. 



