1.C.95 The Pore-forming ESAT-6 Protein (ESAT-6) Family
The ESX-1 secretion system (TC# 9.A.25) plays a critical role in virulence of M. tuberculosis and M. marinum. Virulent M marinum is able to escape from the Mycobacterium-containing vacuole (MCV) into the host cell cytosol, polymerize actin, and spread from cell to cell. ESX-1 plays an essential role in M. marinum escape from the MCV.
Smith et al. (2008) provided evidence that M. marinum induces membrane pores approximately 4.5 nm in diameter, and this activity correlates with ESAT-6 secretion. Purified ESTAT-6, but not the other ESX-1-secreted proteins, is able to cause dose-dependent pore formation in host cell membranes.
The reaction catalyzed for ESAT-6 is:
molecules (vacuoles) molecules (cytoplasm)