Figure 1. Cotranscription of alr-gcp gene cluster as determined by RT-PCR.

(A–D) Total RNA from M. tuberculosis H37Rv in exponential phase was reverse transcribed and the cDNA thus made was used as template for PCR. Primers were designed in order to amplify the junctions between adjacent genes, shown above each gel. Each panel is constituted by three lanes – gDNA lane, which contains amplified product from genomic DNA and serves as positive control; RT+ lane, contains PCR product from cDNA; RT− lane, the negative control, represents the PCR product from possible gDNA present as contaminant in RNA preparation used for cDNA synthesis. (E) A schematic representation of the position of primers designed for cotranscription analysis of the gene cluster.