This project aimed to investigate the effects of glyphosate-based herbicide Roundup LB Plus on bacteria. For this, ten environmental strains of Salmonella enterica were exposed to the increasing concentrations of Roundup over several passages to obtain Roundup-resistant mutants. Four stable re-sequenced resistant mutants and their respective ancestors were characterized by global proteomics in the presence and absence of sub-inhibitory (1/4xMIC) concentrations of the herbicide. By comparing the proteomes of the Roundup-challenged ancestors with constitutive non-challenged ancestors, it became possible to deepen the understanding of how Roundup stress affects naïve bacteria. Similarly, comparing Mutants versus Ancestors in the absence of Roundup allowed to understand how Roundup resistance constitutively affects bacterial physiology, while the comparison of Roundup-challenged mutants versus constitutive mutants helped improve the understanding of the inducible responses in the resistant background.