506 A MANUAL OF BACTERIOLOGY 



man, particularly in subjects who have received a single 

 prophylactic dose of tetanus antitoxin after the occur- 

 rence of a dirty wound. 



The fowl and cold-blooded animals are immune to the 

 toxin. 



Toxins. Cultivated anaerobically in broth, the tetanus 

 bacillus forms a most potent extra-cellular toxin, so that 

 if the culture be filtered through a porcelain filter, 0-001 

 c.c., 0-0001 c.c., or even 0-00001 c.c. of the filtrate is a fatal 

 dose for a guinea-pig. 



Tetanus toxin broth contains a tetanising substance, 

 termed tetano-spasmin, and also a hsemolysin, tetano- 

 lysin. The toxin has a special affinity for nerve-tissue 

 (seep. 185). 



By treatment with carbon disulphide, tetanus toxin 

 broth becomes practically non-toxic, though it still retains 

 its power of immunising on inoculation and of combining 

 with antitoxin that is to say, bodies are formed analogous 

 to the toxoids of diphtheria toxin. 



Brieger, from impure cultures of the tetanus bacillus, 

 obtained two basic bodies which he termed " tetanine " 

 and " tetano -toxin," the former producing tetanic symp- 

 toms in mice, and the latter tremor, paralysis, and finally 

 convulsions. Brieger also isolated tetanine from the 

 amputated limb of a tetanic patient. Brieger and Frankel 

 obtained a tox-albumin from bouillon cultures which 

 induced tetanus in guinea-pigs. Brieger and Cohn subse- 

 quently investigated the tetanus poison obtained by pre- 

 cipitating veal-broth cultures with ammonium sulphate 

 added to saturation, and purifying by re-dissolving, preci- 

 pitating the protein with basic lead acetate, and removing 

 other soluble impurities by dialysis. The purified product 

 forms yellow flakes, soluble in water, but not giving the 

 Millon and xanthoproteic reactions. It is not precipi- 

 tated by most metallic salts, and is not carried down by 



