Schematic representations showing the positions of the RT-PCR primers in the exoY promoter region in A and a picture showing the RT-PCR products in B. A: Line graphs showing the exoY promoter region, the positions of proposed exoY promoters, the predicted transcripts, the areas the RT-PCR primer anneals to, and the exoY promoter area in the plasmids used in the study. B: A picture of agarose gel showing DNA size standard (lane 1), RT-PCR products from cells carry plasmid pHC201 (lane 2), pHC207 (lane 3), pHC208 (lane 4), pHC214 (lane 5), and pHC215 (lane 6).