TOXINS OR TOXALBUMINS 43 



Most toxins are easily decomposed by sunlight, air, and heat. 

 Absolute alcohol separates the active principles from the bouillon 

 in which it grows. Ammonium sulphate also precipitates the 

 toxins from cultures of tetanus and diphtheria bacilli, from which 

 they may be collected, dried and powdered, and in this state 

 may be kept much longer without deteriorating into inert sub- 

 stances. Small quantities of bile and pancreatic juice destroy 

 the toxic properties of diphtheria and tetanus toxin. 



Since the toxins cannot be isolated in a chemically pure form, 

 their exact composition cannot be known, except by studying 

 their effects upon animals and animal tissues. Hence, when anti- 

 toxin, added to toxin in a test-tube is injected into an animal, 

 and no harm results, it is rightly assumed that the toxin is 

 neutralized, and both are chemically bound; yet if fresh toxin is 

 added to the mixture, it is no longer neutral. 



If the toxin of the pyocyaneus and the anti-toxin be mixed so 

 that they neutralize each other, and if the mixture is heated, the 

 neutralization disappears, and the mixture becomes toxic again. 

 That the union is a chemical one, may be inferred from the fact 

 that it is more rapid in concentrated solution than in weak, and 

 is much quicker when warmed than when cold, and it follows the 

 law of multiples, i part toxin neutralizing i part of anti- toxin, 

 and 10 parts of toxin neutralizing 10 parts of anti- toxin. All 

 this is in accord with chemical laws. Toxins sometimes degener- 

 ate into what Ehrlich has called toxoids, substances that bind 

 (unite with) anti-toxin just as effectively as toxins, while they 

 are not poisonous, yet may stimulate healthy cells to secrete 

 anti- toxins if they are injected into the body of experiment 

 animals. 



More is known about the toxins of diphtheria and tetanus bacilli 

 than of any other. Diphtheria toxin has numerous component 

 substances, one of which is the toxin that causes the acute phe- 

 nomena of diphtheria intoxication. Another, toxon, causes 

 cachexia and paralysis some time after infection. 



