TUBERCLE BACILLUS 435 



to other guinea-pigs; consequently it is necessary to inoculate a 

 second set of guinea-pigs from the tubercles developing in the first 

 set of pigs in order to be certain that the bacilli are killed. 



Products of Growth. Enzymes. Tubercle bacilli do not produce 

 soluble proteolytic enzymes. No carbohydrate-splitting enzymes 

 have been observed. 



Carriere, 1 Wells and Corper 2 have shown that the bodies of tubercle 

 bacilli contain a lipase of moderate activity. Kendall Walker and 

 Day 3 have demonstrated that the filtrates of cultures of human and 

 bovine tubercle bacilli contain a soluble esterase; the action of the 

 enzyme upon fats is relatively slight. This esterase is produced in 

 an active form in media of very simple composition. 4 



Winternitz and Meloy 5 have shown that the lipase (esterase ?) 

 activity of the blood is decreased in tuberculosis. Bauer states it is 

 increased in the early stages of the disease. 



Hemolysis. Raybaud and Hawthorn 6 state that cultures of tubercle 

 bacilli will not hemolyze the erythrocytes of normal guinea-pigs; the 

 erythrocytes of tuberculous pigs are hemolyzed. 



Tubercle bacilli do not form indol or the ordinary products of bac- 

 terial decomposition in ordinary media. They do not liquefy gelatin 

 nor do they coagulate milk. Theobald Smith 7 has called attention 

 to a very constant differential character between the human and 

 bovine types of the tubercle bacillus. In glycerin broth the human 

 tubercle bacillus causes a permanent acid reaction, while the bovine 

 bacillus under the same conditions causes the medium to become 

 alkaline if the growth conditions are suitable. Tuberculin prepared 

 from human cultures consequently is acid in reaction, while that 

 prepared from bovine cultures is alkaline. The organism liberates 

 a moderate amount of ammonia incidental to its metabolism of pro- 

 teins or amino acids. 8 Old cultures of tubercle bacilli occasionally 

 are very gelatinous. 9 Vaughan, 10 White and Avery 11 and White, 12 using 



1 Compt. rend. Soc. Biol., 1901, liii, 320. 



2 Jour. Inf. Dis., 1912, xi, 388. 



3 Ibid., 1914, xv, 443. 



4 Kendall, Walker and Day, Jour. Inf. Dis., 1914, xv, 455. 



5 Jour. Med. Research, 1910, xxii, 107. 



6 Compt. rend. Soc. Biol., 1903, No. 55. 



7 Trans. Am. Phys., 1903, xviii, 108; Am. Jour. Med. Sc., 1904, cxxviii, 216; Jour. 

 Med. Research, 1905, xiii, 253, 405. 



8 Kendall, Day and Walker, Jour. Inf. Dis., 1914, xv, 417, 423, 428, 433. 



9 Weleminsky, Berl. klin. Wchnschr., 1912, xlix, 1320. Gotzl, Wien. klin. Wchnschr. 

 1913, 1614. Kendall, Day and Walker, Jour. Inf. Dis., 1914, xv, 428. 



10 Protein Split Products, 1913. 



11 Jour. Med. Research, 1912, xxvi, 317. 



12 Trans. 9th Ann. Meet. Nat'l. Assn. Study and Preven. Tuberculosis. 



