806 PATHOGENIC MICROORGANISMS 



The toxins proper of B. pyocyaneus have been the subject of 

 much investigation, chiefly by Wasserrnann. 35 Wassermann found 

 that filtrates of old cultures were far more poisonous for guinea-pigs 

 than extracts made of dead bacteria. He concludes from this and 

 other observations that B. pyocyaneus produces both an eudotoxin 

 and a soluble secreted toxin. The toxin is comparatively ther- 

 mostable, resisting 100 C. for a short time. Animals actively im- 

 munized with living cultures of B. pyocyaneus give rise in their 

 blood serum to bacteriolytic antibodies only. Immunized with 

 filtrates from old cultures, on the other hand, their serum will 

 contain both bacteriolytic and antitoxic substances. The true toxin 

 of B. pyocyaneus never approaches in strength that of diphtheria 

 or of tetanus. Active immunization of animals must be done care- 

 fully if it is desired to produce an immune serum, since repeated 

 injections cause great emaciation and general loss of strength. 

 Specific agglutinins have be'en found in immune sera by Wasser- 

 mann 36 and others. Eisenberg 37 claims that such agglutinins are 

 active also against some of the fluorescent intestinal bacteria. 



Bulloch and Hunter 38 have recently been able to show that old 

 broth cultures of B. pyocyaneus contain a substance capable of 

 hemolyzing the red blood corpuscles of dogs, rabbits, and sheep. 

 This "pyocyanolysin" seems intimately attached to the bacterial 

 body. Prolonged heating of cultures does not destroy it. Heating 

 of hemolytic filtrates, however, destroys it in a short time. The 

 filtration of young cultures yields very little pyocyanolysin in the 

 filtrate. In old cultures, however, a considerable amount passes 

 into the filtrate. Whether or not the hemolytic power is due to 

 a specific bacterial product or is dependent upon changes in the 

 culture fluid, such as alkalinization, etc., can not yet be regarded 

 as certain. 



Gheorghiewski 39 claims to have found a leucocyte-destroying 

 ferment in pyocyaneus cultures. 



35 Wassermann, Zeit. f. Hyg., xxii, 1896. 



36 Wassermann, Zeit. f. Hyg., 1902. 



37 Eisenberg, Cent. f. Bakt., 1903. 



38 Bulloch imd Hunter, Cent. f. Bakt., xxviii, 1900. 



39 GheorghiewsJci, Ann. de 1'inst. Pasteur, xiii, 1899- 



