MANUAL OF BACTERIOLOGY. 



of tetanus, endotoxins, have been obtained from the spirillum of cholera, the 

 bacillus of typhoid fever, the Bacillus coli communis, the bacillus of bubonic 

 plague, Bacillus pyocyaneus; Streptococcus pyogenes, and Staphylococcus py- 

 ogenes aureus. The extract from cultures of tubercle bacilli, called tuberculin, 

 and that from glanders bacilli, called mallein, will be spoken of in connection 

 with the bacteria themselves. Besides these toxic substances, lysins or bodies 

 which disintegrate bacteria and other substances have been obtained from bac- 

 terial cultures. Thus pyocyanase disintegrates many kinds of bacteria (see p. ). 

 Some bacteria seem to contain lysins which disintegrate the bacteria themselves 

 in which they are produced so-called autolysins. Vaughan * has succeeded 

 in cultivating anthrax bacilli, colon bacilli, and other bacteria on large surfaces 

 of solid media, so as to secure quantities of the bacterial cells sufficient for exten- 

 sive chemical tests. The toxin of the colon bacillus proved to be a very stable 

 substance, and resistant to heat. Most toxins become inactive at comparatively 

 low temperatures (60 to 70 C.). 



The endotoxin of plague f is destroyed by 70 C. ; that of dysentery by 80 C., 

 that of typhoid by 127 C. 



Other physiological properties of the toxins will be brought out in connection 

 with the discussion of immunity. 



There is good reason on both clinical and experimental grounds to believe 

 that toxic substances are formed by the Micrococcus lanceolatus of pneumonia. 



In connection with bacterial poisons another class of bodies 

 may be conveniently described; these are agglutinins, lysins 

 and precipitins. 



Agglutinins. The blood-serum of human beings as well 

 as of animals suffering from certain diseases has the power 

 of causing the bacteria of the disease from which the individual 

 has recovered to clump into larger or smaller masses in liquid 

 cultures to which the serum is added. The same phenomenon 

 is observed in the serum of animals injected with repeated 

 doses of cultures. This is due to certain substances called 

 agglutinins. The reaction, while it is more or less specific, 

 is not as strictly so as was formerly thought, for it has been 

 found that a given agglutinin may cause clumping of a group 

 of nearly related bacteria; such an agglutinin is called a group 

 agglutinin; and, moreover, under certain circumstances the 



* Journal American Medical Association. September 3. 1904. 

 tBesredka. Bull, de VInst. Past. No. 13, Vol. IV., July 15, 1906. p. 587. 



