122 CHEMISTRY OF BACTERIA AND THEIR PRODUCTS 



destructive effects (toxophore or zymophore group), while the 

 portion of the molecule that unites with the substance that is to 

 be attacked (haptophore group) remains uninjured, the toxin 

 becoming a toxoid, the enzyme a fermentoid. Enzymes as well 

 as toxins are poisonous when injected into animals, and the 

 animals react to each by producing substances (anti-bodies) that 

 render each inert, probably in the same way. On the other 

 hand, enzymes and toxins seem to produce their effects according 

 to different laws : A small amount of enzyme can in course 

 of time produce an almost indefinite amount of effect, whereas 

 toxins act more nearly quantitatively. It seems as if the 

 enzyme were bound to the body upon which it acts, as is the 

 toxin, but that after it has destroyed this body it is set free in a 

 still active form, ready to accomplish further work, whereas the 

 toxin is either not set free, or it becomes inactive after it has 

 once been combined. 



Agencies Destroying Toxins. Toxins are very susceptible 

 to light, direct sunlight soon destroying the power of toxin 

 solutions. l Oxygen, even dilute as in air, is harmful ; and all 

 oxidizing agents, including oxidizing enzymes, destroy them 

 quickly. Like enzymes, they withstand such antiseptics as 

 chloroform, toluol, etc., and are precipitated by the heavy 

 metals. Some agencies seem to attack only the toxophore portion 

 of the molecule, e. <?., iodin, carbon disulphid (Ehrlich). 



Introduced into the gastro-intestinal tract, most bacterial 

 toxins are not absorbed (botulinus toxin excepted), cause no 

 symptoms, and do not reappear in the feces ; they are therefore 

 destroyed by the contents of the tract, pepsin, pancreatic juice, 

 and bile all being capable of destroying toxins. 2 They may, 

 however, when injected subcutaneously, circulate unimpaired in 

 the blood of non-susceptible animals, gradually disappearing, 

 more through slow processes of destruction than by elimination. 

 When injected into susceptible animals, they soon disappear from 

 the blood, being fixed in the^organs that they attack. 



Differences from Ptomains. While ptomai'ns are formed 

 by cleavage processes from the medium upon which the bacteria 

 grow, and the same ptomai'ns can be produced by several different 

 kinds of bacteria, the toxins are synthetic products of absolutely 



1 Fluorescent substances have a destructive effect upon toxins, even in the 

 animal body, according to lodlbauer and v. Tappeiner, Deut. Arch. klin. Med., 

 1905 (85), 399. 



8 Baldwin and Levene (Jour. Med. Kesearch, 1901 (6), 120) found that diph- 

 theria and tetanus toxin are both destroyed, apparently through digestion, by 

 pepsin, trypsin and papain acting for several days. Keview of Literature by 

 Lust, Hofmeister's Beitr., 1904 (6), 132. 



