Quantitative RT-PCR of Salmonella Typhimurium strains from cultures. Gene expression of select SPI-1 invasion genes measured by RT-qPCR from Salmonella mutants ΔpflB::kan and ΔadhE::kan and comparing expression to the wild-type strain. The 16S rRNA gene was used for normalization. Genes are listed along the X-axis while relative expression level is listed along the Y-axis. Asterisk indicates significance of the mutant strain from the wild-type at p < 0.05 assessed for each gene.