ENZYMES OF THE TUBERCLE BACILLUS 



147 



using the Lewis and Benedict colorimetric picramic acid method. 

 Among four tubes was divided equally 14 cc. of bacillary emul- 

 sion (2 cc. bacillary residue in each). Two of the tubes were 

 heated for thirty minutes at 100°C., in a water bath to destroy 

 the enzymes present. To each of the four tubes was added 

 2 cc. toluene and 1 cc. chloroform and sufficient sterile physio- 

 logical salt solution to make a total volume of 10 cc. of emul- 

 sion. To two of the tubes, one heated and one unheated, was 

 added 5 cc. of 2 per cent sucrose making a concentration of 

 1 per cent sucrose, and to the other two, one heated and one 

 unheated, 5 cc. of freshly prepared arrowroot starch emulsion 

 made by adding 2 grams of starch in suspension in cold water 

 to about 75 cc. boiling water and diluting to 100 cc. after 

 cooling. 



After thorough mixing, the tubes were centrifugated and 1 cc. 

 of the solution drawn off and tested for reducing sugar. The 

 tubes were then incubated at 37°C., and 1 cc. withdrawn and 

 tested at various intervals thereafter. ^ The results are given 

 in the following table. 



Starch. 



Sucrose. 



I Xot heated 

 1^ Heated control 



{ Xot heated 

 )^, Heated control 



TIME OF TEST IN DAY3 



Trace (about 0.1 mgm.) 

 Trace (about 0.15 mgm.) 



Trace (about 0.15 mgm.) 

 Trace (about 0.2 mgm.) 



0.2 

 0.2 



0.3 

 0.25 



Summary. Tubercle bacilli do not possess an. enzyme cap- 

 able of hydrolyzing starch or sucrose in sufficient amount to be 

 demonstrable by the method used. 



-' Control tests of 1 per cent starch and 1 per cent sucrose to which had been 

 added chloroform and toluene revealed no difference from a blank test with the 

 reagents alone. Varying amounts of glucose, 0.5, 0.4, 0.3, 0.2, and 0.1 mgm., 

 in 1 cc. water to which had been added toluene and chloroform also revealed no 

 influence of the antiseptics upon the accuracy of the. test. 



