COCCI 103 



onstrated (369, 618). These substances have been considered to be 

 either autotoxins (148) or proteolytic enzymes (719). The filtrate of 

 E. coli was reported (836) to be highly selective in its action, depress- 

 ing only the dysentery organism of Shiga. Gundel (372) isolated from 

 a bouillon culture of E. coli thermostable lipoids capable of bringing 

 about the lysis of the colon organism and other bacteria. The antago- 

 nistic relations between E. coli and V. comma are well established. The 

 cholera organism also possesses antagonistic properties (308, 499). 



The typhoid organism is also capable of exerting an antagonistic ac- 

 tion against itself as well as against Ps. jiuorescenSy E. coli, and various 

 other bacteria, including B. anthracis. The nature of the action is not 

 clearly understood. Salmonella faratyfhi possesses antagonistic proper- 

 ties against E. coli, B. anthracis, P. -pestis, and various other bacteria. 



COCCI 



Numerous cocci have been found to possess antagonistic properties 

 against other bacteria. Doehle (187) first demonstrated in 1889 that 

 streptococci are able to antagonize B. anthracis, especially on solid 

 media. Similar action was exerted against diphtheria bacteria j this ac- 

 tion was not correlated with the hemolytic properties or the virulence 

 of the antagonist. Further studies established the effect of various 

 streptococci against anthrax. This effect was found (no) to be more 

 pronounced in liquid than in solid media, and to be highly specific as 

 regards the strain. S. pyogenes was shown to be antagonistic, in vivo, to 

 B. anthracis and to Phytomonas tumejaciens, even to the extent of sup- 

 pressing vegetative malformations brought about by the last named 

 (70). 5. cremoris was active against S. lactis ( 1007), 5. mastidis against 

 5. lactis and L. acidophilus, and Streptococcus mucosus against P. pestis. 

 Rogers (802) reported an antagonistic effect of S. lactis against L. bul- 

 garicus; the active substance was thermostable and would not pass 

 through a bacterial filter. More recently, certain streptococci were 

 found (625) to produce a very potent antibiotic which was thermo- 

 stable and dialyzablej it was active against various gram-positive but 

 not gram-negative bacteria j it was well tolerated on subcutaneous and 



