Bacillus Pyocyaneus 367 



formation of a third pigment, but the work of Boland * has 

 shown this to be a transformation product of pyocyanin 

 common in old cultures. 



The organism produces a curdling ferment, a fibrin- and 

 casein-dissolving ferment, a gelatin-dissolving ferment, 

 and a bacteriolytic ferment, the pyocyanase of Emmerich 

 and Low. 



It also produces, under favorable conditions, a toxin 

 which has been studied by Wassermann, who found it fatal 

 in doses of 0.2 to 0.5 c.c. when intraperitoneally injected into 

 guinea-pigs. The animals show peritonitis and punctiform 

 hemorrhages on the serous membranes. 



Bullock and Hunter f found that Bacillus pyocyaneus also 

 produces a hemolytic substance, pyocyanolysin, by which 

 corpuscles of man, oxen, sheep, apes, rabbits, cats, rats, 

 dogs, and mice are dissolved. The peculiar substance was 

 produced in greatest quantity in virulent cultures three or 

 four weeks old. JordanJ believes that this hemolytic 

 property of the cultures depends solely upon the intense 

 alkali formed in old pyocyaneus cultures. Gheorghewski 

 found a leukocyte-destroying substance in the cultures. 



In addition to the metabolic pigments mentioned, the or- 

 ganism produces toxins. Wassermann || found that filtrates 

 of old cultures were more toxic for guinea-pigs than the endo- 

 toxins made by lysis of dead bacteria. The organism thus 

 produces both endo- and exotoxins. 



Pathogenesis. The bacillus is pathogenic for the small 

 laboratory animals, but different cultures differ greatly 

 in virulence. One c.c. of a virulent bouillon culture, injected 

 into the subcutaneous tissue of a guinea-pig or a rabbit, 

 caused rapid edema, suppurative inflammation, and death 

 in a short time (twenty-four hours). Sometimes the animal 

 lives for a week or more, then dies. There is a marked 

 hemorrhagic subcutaneous edema at the seat of inoculation. 

 The bacilli can be found in the blood and in most of the 

 tissues. The guinea-pig is most susceptible. 



Doses too small to prove fatal sometimes lead to suppu- 

 ration, and the injection of sterilized cultures leads to simi- 

 lar results, a relatively larger quantity being required. 



* "Centralbl. f. Bakt.," Bd. xxv, 1899, p. 897. 



t Ibid., xxviu, 1900, p. 865. | Ibid., Bd. xxxin, Ref. 1903. 



"Ann. de 1'Inst. Pasteur," 1899, xin. 



|| "Zeitschrift fur Hygiene, 1896, xxn. 



