TETANOLYSIN AND STAPHYLOLYSIN 



Tetanolysin is formed along with the specific toxin, tetano- 

 spasmin, when the B. tetani is grown in broth, the two substances 

 being formed in variable amounts under different circumstances. 

 It is very unstable, disappearing entirely in a day or two at the 

 room temperature, and being destroyed by heating to 50 C. for 

 twenty minutes. It cannot be obtained free from tetanospasmin, 

 but a solution of tetanus toxin can be deprived of its lysin, and 

 only the specific toxin left, by adding some red corpuscles to the 

 solution, kept at a low temperature, and centrifugalizing them 



FIG. 6. A "SATURATION EXPERIMENT" SHOWING THAT H^MOLYSOID HAS 

 THE POWER OF COMBINING WITH RED BLOOD-CORPUSCLES, AND SHIELD- 

 ING THEM FROM THE ACTION OF H^MOLYSIN. (SCHEMATIC.) 



In the first tube the corpuscles are shown in presence of an excess of old 

 or heated haemolysin ; in the second they are washed clear from this 

 excess, and are apparently unaltered ; in the third active haemolysin is 

 added, but the corpuscles are not dissolved, as they would be in a control- 

 tube with normal corpuscles. 



off; the supernatural fluid will contain tetanospasmin, whilst the 

 tetanolysin will have combined with the corpuscles. 



Staphylolysin appears in alkaline cultures on the fourth day, 

 and reaches its maximum between the tenth and twelfth. It is 

 an unstable substance, but more stable than tetanolysin, persist- 

 ing for a fortnight at the room temperature, and requiring a 

 temperature of 56 C. for twenty minutes for its complete destruc- 

 tion and in this case the destruction appears to be really com- 

 plete, for the injection of the heated solution is said not to lead 

 to the production of an antistaphylolysin. Many normal sera, 

 especially those of man and the horse, contain antistaphylolysin ; 



