FIG. 3.
RT-PCR analysis to determine whether the open reading frames in the orf2c gene cluster are part of an operon. The excision gene cluster is shown at the top. Abbreviations are as follows: 2c, orf2c; 2d, orf2d. The locations of the primers used for the RT-PCR analysis are shown below the map, with both primers in the same set given the same fill. The promoter region is indicated as PE. The mRNA was prepared from BT4007, which contains CTnDOT integrated in the chromosome, from cells grown in medium containing 1 μg/ml tetracycline (Tc) (+) or no Tc (−). Portions (5 μl) of the products of the RT-PCRs were electrophoresed on a 2% agarose gel. The sizes in bp of the products are indicated by arrows on either side of the gel. All products were of the expected sizes.