Abstract
We have studied on the isoelectric point (I. E. P. ) of the tubercle baciili with two methods, (1) acid agglutination and (2) electrophoresis; for the latter we have employed the cataphoretic apparatus with three chambers, which has been improved in our own institute.
The bacterial suspensions were thoroughly homogenized and stabilized by the application of supersonic waves under favourable conditions.
The results and conclusions are as follows:—
1. The tubercle bacilli carry negative charge in neutral water media as other nonacidfast bacteria do, and their I. E. P. is near pH = 3
2. The I. E. P. of the tubercle bacilli is considere d as that of the complex-ampholyte which is composed, of defatted bacterial bodies and lipoid substances extracted.
3. The alkaline I. E. P. of the tubercle bacilli lies at pH 13, n either does this value differ from that of other bacteria.
Summing up, we might say t hat the characteristics of the tubercle bacilli are not to be explained with regard to their charge.
