Salmonellae are facultative intracellular bacteria that cause a wide variety of pathogenic disorders in animals and humans. Its transmission is mainly due to consumption of contaminated food and water, and constitutes a serious public health problem, with high impact in developing countries. Salmonella infections also affect a number of economically relevant animals, particularly avian species. This pathogen is able to survive and multiply in different host tissues, as well as in the environment. This versatility is in part due to the presence of Salmonella-specific factors that allow the adaptation to the different harsh conditions this pathogen has to face. The goal of our research is to understand how Salmonella is able to recognize specific environmental signals and to modulate the expression of its gene repertoire in accordance. We are particularly interested in the characterization of Salmonella MerR-like metalloregulators, both those ancestral to the enterobacterial genome like the copper-tolerance master regulator CueR, and those encoded in Salmonella-specific chromosomal regions called genomic islands, such as the gold sensor GolS. Our research is focused in 1) the elucidation of the signal(s) detected by the regulators and the molecular/structural features that guarantee such perception; 2) the characterization of the DNA selection and interaction mechanism that allows the regulators to specifically modulate the expression of their target genes; and 3) to understand the physiological role of each of the gene-products controlled by the transcriptional regulators in study. The knowledge of these processes will allow us to formulate a clear picture of the molecular mechanisms employed by this pathogen in order to adapt to different environments. It will also help to design selective therapeutic strategies against this bacterium, as well as to develop signal-specific expression and delivery systems for heterologous antigens, particularly important in human health and in animals’ production. In parallel, the identification of the environmental signals detected by these detectors will allow the development of specific biosensor systems, with potential impact in biotechnology.