Proteomic analysis of the secretome of a esxaA mutant Mycobacterium tuberculosis strain

Extracellular Mycobacterium tuberculosis (Mtb) aggregates can evade phagocytosis and intracellular host-cell defenses by inducing macrophage killing. We showed that Mtb aggregates require a functional ESX-1 type VII secretion system to induce cell death upon contact with macrophages. We used quantitative proteomics to compare the secretome of a esxA mutant strain with the wild type reference to identify secreted bacteria factors involved in macrophage death induction.