[Effect of surface-active agents on Mycobacterium tuberculosis and Mycobacterium bovis. Obtaining chromogenic...

In 18 strains of M. tuberculosis and M. bovis it has been possible to demonstrate the existence, in pure cultures, of elements able to grow in vitro in scotochromogenic mycobacteria. The experimental method used includes a dispersion, under shaking, of organisms in different surface-active agents. The chromogenic strains isolated during the experimentation are eugonic, and PAS- and INH-resistant. Their experimental virulence is different from that of tubercle bacillus. We discuss the signification of this dissociation phenomenon inductible by surface-active agents.