FIGURE 1.

Effect of H₂O₂ on gene transcription of E. coli O157:H7. Relative gene transcription represents the change in transcription compared to the bacteria without H₂O₂ treatment (control, value of 1.0). The transcription of each gene was normalized to the 16S rRNA transcription in each sample. Data are expressed as the means ± SE for RNA extracted in three biological replicates. × denotes no transcription of soxR by E. coli O157:H7 after exposure to H₂O₂ on lettuce, however, soxR is present in this strain. ^∗denotes the significant change of gene transcription between treatment and control.