FIG 1.

STM1344 might play a more critical role than STM1697 in the late phase of Salmonella infection. (A and B) The transcription levels of STM1344 and STM1697 in Salmonella before and after invasion of HT-29 and RAW264.7 cells were detected by qRT-PCR. gapA (glyceraldehyde-3-phosphate dehydrogenase A) was used as a loading control. (C) Intracellular survival capability of WT, Δstm1344, and Δstm1697 strains in RAW264.7 cells at 2, 4, and 6 h postinfection. (D) Caspase-1 activity of RAW264.7 cells infected with the above strains after 2, 4, and 6 h postinfection. ***, P < 0.001; **, P < 0.01; *, P < 0.05.