TABLE 3.

qRT-PCR of selected invasion and virulence genesa

LocusbNamePrimer sequencecFragment size (bp)dRatioe
STM2893invI5′-CTTCGCTATCAGGATGAGG-3′161−9.27
5′-CGAACAATAGACTGCTTACG-3′
STM2874prgH5′-GGCTCGTCAGGTTTTAGC-3′190−8.45
5′-CTTGCTCATCGTGTTTCG-3′
STM2871prgK5′-ATTCGCTGGTATCGTCTCC-3′199−8.56
5′-GAACCTCGTTCATATACGG-3′
STM2886sicA5′-GATTACACCATGGGACTGG-3′207−3.92
5′-CAGAGACTCATCTTCAGTACG-3′
STM1593srfA5′-AGGCGGCATTTAGTCAGG-3′176−4.33
5′-GACAGGTAAGCTCCACAGC-3′
STM1594srfB5′-GGTACCAGAAATACAGATGG-3′190−6.55
5′-GCCGATATCAATCGATGC-3′
  • a STM3211 (rpoD) was used as the reference gene where no significant change in expression level was observed. The primer sequences used for rpoD were as follows: 5′-CGATGTCTCTGAAGAAGTGC-3′ (forward) and 5′-TTCAACCATCTCTTTCTTCG-3′ (reverse). The size of the fragment generated was 150 bp.

  • b Location of the ORF in the serovar Typhimurium LT2 genome.

  • c For each set, the first sequence is the forward primer, and the second sequence is the reverse primer.

  • d Size of the amplified PCR product.

  • e Ratio of transcription levels in the fnr mutant to those in the WT.