ENZYMES OF THE TUBERCLE BACILLUS 141 



These results indicate a definite splitting of the casein by the 

 autolysate withdrawn at the third day of autolysis, but sub- 

 sequently the enzymes have either been entirely washed away 

 from the bacilli or have been so diluted by the additional salt 

 solution added that they are incapable of exerting any action 

 upon the casein. 



Experiment II. By the non-coagulable nitrogen liberated in 

 alkaline solution. Tubercle bacilli, 4 cc. of a heavy emulsion, 

 were placed in 15 cc. graduated centrifuge tubes (2 cc. in each). 

 One as control was heated to kill the bacilli, and to both was 

 added 10 cc. physiological salt solution, sufficient sodium car- 

 bonate to make 0.3 per cent, 2 cc. toluene and 1 cc. chloroform. 

 The tubes were then placed in the incubator at 37°C., after 

 withdrawing 1 cc. as a control test, and 1 cc. of the clear super- 

 natant solution was withdrawn after centrifugation daily, for 

 eight days. The non-coagulable nitrogen was determined as 

 before by the Fohn micro-method. 



Test 



Heated control. 



0.12 0.12 0.13 0.13 0.14 0.14 0.15 0.16 0.17 



0.1l'0.11O.110.10'0.11O.12 0.12 0.1l'0.12 



I I I I I I I I 



RE81DUAI, 

 NITROGEN 



mgm. 



4.26 

 4.8 



The figures are given in milligrams of nitrogen per cubic centimeter 



These figures indicate that there is present in tubercle bacilli 

 an enzyme capable of decomposing the nitrogenous constituents 

 of the bacillary bodies in alkaline solution. 



Experiment III. By the amino acid a nitrogen liberated in 

 alkaline solution. The above experiment (II) was repeated in 

 all details except that the solution was freed from coagulable 

 proteins by means of fifteen volumes of methyl alcohol, the 

 alcohol evaporated off from the filtrate, the residue taken up 

 by 2 cc. distilled water and this tested quantitatively for amino 

 acid a nitrogen content. The following results were obtained, the 

 figures being given in milligrams amino acids using asparagin 

 as the standard. 



