Deletion of mce2R from M. tuberculosis. A. PCR reactions to confirm the allelic replacement in MtΔmce2R. Primers were designed to amplify either an internal mce2R region (Primers WT) or the mutant allele (Primers KO). Molecular weight markers (M) are shown on the left. C- is negative PCR control. The expected molecular weights of the bands are indicated. B. Schematic representation of the wild type H37Rv and the mutant MtΔmce2R. The position of each pair of primers is indicated with arrows.