Abstract
Background: Mycolic acid cyclopropanation plays an important role in mycobacterial virulence but molecular mechanisms controlling cyclopropanation remain unknown. Results: Phosphorylation of the cyclopropane synthase PcaA decreases mycolic acid cyclopropanation and intracellular survival and abrogates the phagosome maturation block (PMB). Conclusion: PMB modulation is dependent on mycobacterial protein phosphorylation. Significance: This study highlights Ser/Thr-dependent phosphorylation of a mycolic acid biosynthetic enzyme in mycobacte-rial virulence.