My research started in 1981 in the Unité de Biochimie Cellulaire directed by Georges Cohen (Institut Pasteur, Paris), where I worked on the branched biosynthetic pathway leading to the amino acids Lys, Met, Thr and Ile; we found that enzymes catalyzing different steps in this pathway have a common origin, thereby providing evidence that amino acid biosynthetic pathways have been constructed by specialization of enzymes exhibiting a substrate ambiguity.
In 1988, I joined the laboratory of John Mekalanos (Harvard Medical School, Boston), where I studied for two years the regulation of virulence genes in Vibrio cholerae; we performed a functional analysis of genes co-regulated with cholera toxin-encoding genes and demonstrated a regulatory cascade controlling their expression.
In 1990, I joined the newly created Unité de Pathogénie Microbienne Moléculaire directed by Philippe Sansonetti (Institut Pasteur, Paris), where I investigated virulence factors of Shigella flexneri. Over the last 20 years, I headed a group composed of one or two PhD students, a post-doctoral fellow and, since 2003, a technician. Our works participated to the discovery of the type III secretion (T3S) pathway used by many Gram-negative bacteria to inject effector proteins into host cells and alter their signaling pathways.
From January 2010 to December 2014, I occupied the function of Vice-President for Teaching at Institut Pasteur.