Invasion of A549 epithelial cells by B. pseudomallei. A549 cells were infected with overnight cultures of B. pseudomallei K96243 at MOI of 100, SDO mutant, and complement strains grown in NaCl-free LB broth, LB broth with 150 mM NaCl, or LB broth with 300 mM. Intracellular bacteria were counted after lysing infected cells at 4 hrs post-infection. Asterisks indicate significant differences (p-value ≤ 0.05, t-test) between groups. Error bars represent standard errors of mean for experiments performed in triplicate.