The tuberculosis pathogen releases its toxin by a novel protein transport system

Six years ago, researchers described the first toxin ever found for the deadly pathogen Mycobacterium tuberculosis. However, the mechanism for its secretion from the bacterium was unknown. Now, researchers describe two small Esx proteins that form pores in bacterial membranes and are essential for toxin release. This transport system may be widespread across many Gram-positive bacteria that contain proteins in the WXG100 super-family.