The success of rifampin as anti-tuberculosis therapy indicates that the inhibition of RNA polymerase (RNAP) of Mycobacterium tuberculosis (MtbRNAP) is an effective strategy, however, resistance to this antibiotic is increasing. This is why, the finding of new inhibitors for MtbRNAP would be a great contribution to the fight against tuberculosis. Microcin J25 (MccJ25) is an antibiotic peptide whose main molecular target is the RNA polymerase of Escherichia coli (EcoRNAP). Biochemical studies have determined that MccJ25 binds and obstructs the secondary channel of EcoRNAP, in addition, have identified the regions of MccJ25 that are responsible for this interaction. They also demonstrated that MccJ25 inhibits RNA polymerases from bacteria phylogenetically related to E.coli, but has no inhibitory activity on the RNAPs of bacteria related to the Mycobacterium genus. The computational analysis...