Transcriptional linkage between <i>phhA</i> and <i>letA</i>.

<p>(A) The gray horizontal arrows denote the <i>phhA</i> and <i>letA</i> genes. The thin horizontal lines below the genes signify the approximate size and location of transcripts identified by RT-PCR analysis, including an intergenic transcript. (B) Wild-type strain 130b was grown in BYE at 37°C, and then RNA was analyzed by RT-PCR utilizing primer pairs specific to either <i>phhA, letA,</i> or the intergenic region spanning <i>phhA</i> and <i>letA</i>. That the PCR products obtained resulted from mRNA templates was confirmed by the lack of product obtained when the PCR did not incorporate RT (-RT). PCR products obtained from genomic DNA appear in the left-most lanes, indicating that the mRNAs observed are full-length. The results presented are representative of at least three independent experiments.