RESEARCH

Infections with non-typhoidal Salmonella still represent a global health burden, causing 93.8 million cases of gastroenteritis and 155,000 deaths in the world each year. Of particular concern is the rise of infections with antibiotic-resistant serotypes, that are now estimated to 212,500 cases and 70 deaths per year in the United States, and the expansion of invasive strains responsible for more than 681,000 deaths in the world yearly. Therefore, there is an urgent need to better understand the basics of Salmonella pathogenesis in order to identify new targets for drug development.

The ability of Salmonella to cause disease largely depends on mounting the appropriate response to stresses encountered both outside and inside the host in order for the bacteria to adapt to these insults. My group seeks answers to fundamental bacterial physiology and pathogenesis questions with the aim of better understanding how Salmonella, and other pathogens, regulate and fine-tune the activity of their stress response and virulence pathways to cause disease.

Signal transduction

Salmonella's ability to adapt to new environments largely depends on signal transduction pathways that allow the bacteria to reprogram gene expression in response to stress conditions encountered outside the host and during the course of infection. We want to understand how the regulation of these pathways and of their regulon allow Salmonella to adapt to environmental stresses and cause disease.

Regulatory RNAs

Regulatory RNAs are important constituents of bacterial stress response by post-transcriptionally reprogramming gene expression in response to environmental insults. We elucidate the role they play in controlling Salmonella's physiology and how they regulate gene expression.

Small proteins

Small proteins (50 amino acids or fewer) regulate key cellular aspects in bacteria. We are characterizing the function of novel small proteins in Salmonella and are particularly interested in understanding how they modulate the activity of signal transduction pathways involved in virulence and stress response.

Riboswitch ligands biology

Riboswitches are cis-acting regulatory elements found in the 5′-untranslated region of messenger RNAs, where they sense metabolites and regulate gene expression. While most riboswitches characterized to date recognize compounds with well-established biological function (e.g. amino acids, RNA precursors, sugars, cofactors and others), some widespread riboswitch classes bind ligands whose physiological relevance still remains elusive. Using Salmonella enterica as model organism, we aim to elucidate the role these compounds play in bacterial lifestyle and to uncover novel stress response pathways maintaining their homeostasis.