Why macrophages cannot LAP up TB

Figures & data

Figure 5. CpsA inhibits phagosomal recruitment of NADPH oxidase and prevents LAP. WT M. tuberculosis (left) exports CpsA, which prevents recruitment of the NADPH oxidase (which is composed of subunits CYBA/p22^phox, CYBB/gp91^phox/NOX2, NCF4/p40^phox, NCF1/p47^phox, NCF2/p67^phox). The NADPH oxidase is activated by GTP-bound RAC1-RAC2 and is stabilized by RUBCN. When CpsA is lacking (right), the NADPH oxidase is recruited to the phagosome, which results in ROS production. Subsequently LC3 is recruited to the phagosomal membrane through the ATG conjugation system (ATG5, ATG7, ATG12, ATG16L1, and others). The LAPosome matures and is delivered to the lysosome, which depends upon RAB7. Proteins in red are those that are required for macrophages to kill the ∆cpsA mutant.