BACILLUS PYOCYANEUS 581 



Bulloch and Hunter l 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 2 claims to have found a leucocyte-destroying ferment 

 in pyocyaneus cultures. 



1 Bulloch und Hunter, Cent. f. Bakt., xxviii, 1900. 



2 Gheorghiewski, Ann. de 1'inst. Pasteur, xiii, 1899. 



