The role of mycobacterial ESX-1 secretion systems in phagosome escape

In phagosome escape of pathogenic mycobacteria the role of type VII secretion systems (T7SS) seems to be very important. These systems and, in particular, the structural and functional variability of T7SS substrates belonging to the WXG100 superfamily are the focus of our research. The best studied example of Esx protein complex is the Mycobacterium tuberculosis pair ESAT-6 and CFP-10. The current model states that the secreted substrate ESAT-6 is required for membrane permeabilization whereas CFP-10 acts as a chaperone.