CHROMOGENS I2 Q 



the treatment of various intestinal troubles. North has used cultures of B bulgaricus 

 for extermination of undesirable organisms in other parts of the body than the 

 alimentary canal (used as applications in nasal, throat or genito-urinary infections). 



CHROMOGENIC BACILLI 



These are identified by the color of their colonies on agar. The 

 B. pyocyaneus is the most important one of them in medicine, but the 

 B. prodigiosus is also of interest medically. A violet chromogen, the 

 B. yiolaceus, which is motile and liquefies gelatin, has been described 

 under many names. It has been found in water. 



An orange-yellow chromogen, the B. fulvus, is nonmotile and varies as to its 

 liquefaction of gelatin. 



B. pyocyaneus (Gessard, 1882). This organism is frequently termed 

 the bacillus of green or blue pus. It is a small (2. 5X0.5/4) motile 

 Gram-negative bacillus. 



It is generally a slender delicate bacillus often showing thread-like 

 arrangement but at times it may appear as short plump rods. It grows 

 readily at room or incubator temperature. It liquefies gelatin rapidly. 

 The green color diffuses through the agar or gelatin on which it grows, 

 so that we not only have the green-colored colony, but the medium as 

 well is colored. Upon potato the colonies are more of a deep olive 

 green to dirty brown. 



No gas is produced in either glucose or lactose bouillon; blood-serum is digested, 

 the pitted surface showing a reddish-brown color. The protein ferment pyocyanase 

 has been used to remove diphtheritic membrane and for treatment of M, catarrhalis 

 nasal catarrhs. There are 2 pigments a green water soluble one and a blue 

 one soluble in chloroform. 



It is widely distributed in water and air, and is frequently isolated 

 from faeces. The B. fluorescens liquefaciens of water seems to be simply 

 a strain of B. pyocyaneus. The B. pyocyaneus is frequently associated 

 with other pus organisms in abdominal abscesses. 



In addition to having an endotoxin, it produces a soluble toxin similar to diph- 

 theria toxin. This toxin differs from those of diphtheria and tetanus in that it can 

 stand a temperature of iooC., while those of diphtheria and tetanus are destroyed 

 at about 65C. The fact that the union between toxin and antitoxin is only of a 

 binding, neutralizing nature is best shown by taking a mixture of pyocyaneus toxin 

 and antitoxin which is innocuous and heating it. This destroys the antitoxin, but 

 does not injure the toxin. We now find that the original toxicity has returned. The 

 antitoxins of diphtheria and tetanus are more stable than the corresponding toxins; 

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