PATHOGENIC BACTERIA 259 



The above graphic representation shows the benzol mole- 

 cule having a central group of Ce with lateral side chains of H 

 connecting with each atom of C. When one of these side 

 chains of H is replaced by COOH, benzol is converted into 

 benzoic acid. If to this acid radical Na is united, supplanting 

 an H in the OOH of this radical, sodium benzoate is produced. 



When toxins are generated in the body by pathogenic bac- 

 teria or when they are introduced artificially for the purpose 

 of producing active immunity, the toxin molecule combines 

 with the various side chains of the cells. There is first a chemi- 

 cal combination between that chemical group of the toxin 

 molecule, which is known as the haptophore, with a corre- 

 sponding group (side chain) in the cell known as the hapto- 

 phile. Later the so-called chemical toxophore group of the 

 toxin molecule unites with the corresponding group (side chain) 

 in the cell called a toxophile group. The union of the toxin 

 with the cells is a definite chemical union which is stable in 

 some cases (tetanus) and not so stable in others (diphtheria). 

 The cell is usually stimulated only when the haptophore group 

 unites with it, and is injured only when, in addition, the toxo- 

 phore group unites with it. The union of the toxin molecules 

 with the various cells of the body for which it possesses an 

 affinity, causes a reaction and an increased generation of 

 chemical side chains, not in the cell injured, as was first 

 thought, but by cells which have been indirectly injured by the 

 removal from active work of those cells injured by the toxin 

 molecule. In other words, there has been a compensatory 



