Since PAO1, PAK, and PA14 were isolated more than 40 years ago and have been passaged a great deal in laboratories, we studied, at both 37°C and 30°C, the bactericidal effect of the S. maltophilia T4SS and effectors 14245 and 14255 against four strains of P. aeruginosa that were recently isolated from the lungs of four CF patients. The gene discussed is SMOX; the disease is cystic fibrosis.