Genetic organization of the mle locus. A: RT-PCR analysis of mRNA transcripts. The solid arrows indicate the primers used for RT-PCR. The minus RT control is assigned with "-"; the positive control, using genomic DNA, is assigned with "+". B: Gelshift analysis of the region between mleS and mleR. Arrows indicate primers that were used to amplify PCR products, that were subsequently used for EMSA. Primers are designated at their 5' end. The box shows a representative selection of gel shift assays with the respective fragment in the presence or absence of L-malate. Thin arrows indicate DNA fragments in the absence of protein. Bold arrows indicate DNA in complex with MleR. Competitor DNA is marked with an asterix. For all EMSAs, 1× binding buffer was loaded on the left and MleR protein on the right lane. In all EMSAs without malate, an internal fragment of mleS was used as competitor DNA. In EMSAs with malate the fragment within the IGS of mleR and Smu.136c, generated by hybridising primers EP10/11 was used (except for EMSA 5, where the internal fragment of mleS was added).