Martín Gómez, HelenaJorba, MartaAlbericio Palomera, FernandoViñas, MiquelTulla-Puche, Judit2020-09-102020-09-102019-10-02https://hdl.handle.net/2445/170448In this study, microcin J25, a potent antimicrobial lasso peptide that acts on Gram-negative bacteria, was subjected to a harsh treatment with a base in order to interrogate its stability and mechanism of action and explore its structure-activity relationship. Despite the high stability reported for this lasso peptide, the chemical treatment led to the detection of a new product. Structural studies revealed that this product retained the lasso topology, but showed no antimicrobial activity due to the epimerization of a key residue for the activity. Further microbiological assays also demonstrated that it showed a high synergistic effect with colistin.14 p.application/pdfengcc by (c) Martín Gómez, Helena et al., 2019http://creativecommons.org/licenses/by/3.0/es/PèptidsAntibiòticsPeptidesAntibioticsinfo:eu-repo/semantics/article2020-09-08info:eu-repo/semantics/openAccess31627419