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yeast. BX-795 mouse Genetics 1996,144(4):1425–1436.PubMed Competing interests The authors declare that they have no competing interests. Authors’ contributions JEB generated the constructs and strains used, performed most of the analyses, contributed to the design of the study and drafted the manuscript. TI performed the qRT-PCR and contributed to the protein sample preparations and bacterial competition assays. SNW contributed to the design of the study. AS contributed to the design of the study and drafted the manuscript. All authors read and approved the final manuscript.”
“Background Microcin J25 (MccJ25) is a 2,107-Da peptide antibiotic which is constituted by 21 unmodified amino acids and is excreted to the culture medium by E. coli strains harboring the MccJ25-coding plasmid [1, 2]. Uptake of this selleck inhibitor antibiotic into E. coli is dependent on the outer-membrane receptor FhuA [3] and the inner membrane proteins TonB, ExbB, ExbD, and SbmA [4]. Energy provided by the proton motive force of the cytoplasmic membrane and the TonB–ExbB–ExbD protein complex is required for active transport through FhuA [5]. Metalloexopeptidase Once inside the sensitive cell, the peptide is able to inhibit E. coli RNA polymerase (RNAP) and the membrane respiratory chain [6–8]. This antibiotic is active against bacteria related
to the producer strain such as Salmonella, Shigella and E. coli, while other Enterobacteriaceae are resistant [9]. Then, it is possible to say that MccJ25 shows, in vitro, a narrow action spectrum. Currently, we are interested in MccJ25 action on Salmonella, a facultative intracellular pathogen responsible for a variety of diseases in a wide range of animal species. In humans, this pathogen may cause gastroenteritis (food poisoning), septicemia and typhoid fever. Several Salmonella enterica strains showed high sensitivity to MccJ25, while others like S. Typhimurium, S. Derby, and some S. Enteritidis strains were completely resistant [9]. Since, transforming resistant Salmonella strains with a plasmid coding for the E.