Margarita Martínez Medina (born 1979 in Castell-Platja d'Aro) is a researcher in the Microbiology of Intestinal Disease research group of the Department of Biology and a professor in the area of Microbiology since 2001. She obtained her PhD in Biology at the University of Girona (2009) with a thesis focused on the study of microbial populations associated with Crohn's disease, especially Escherichia coli and the pathotype AIEC. During this period she carried out two international research stays. The thesis has received two awards and European mention. In 2010 she began a postdoctoral stay in the laboratory 'Microbes, Intestin, Inflammation et Susceptibilité de l'Hôte' of the Université d'Auvergne (France), a leading multidisciplinary group in research related to the AIEC pathotype. During the post-doc she learned new methodological approaches to the study of host-pathogen relationships and she studied the impact of diet on intestinal homeostasis. In 2019, she was awarded a permanent contract as an associate professor at the Universitat de Girona. Currently, her research is mainly focused on studying the genetic mechanisms involved in the pathogenicity of the AIEC, from a genomic, transcriptomic and functional approach. She is also interested in characterizing new treatments based on new molecules and/or combinations of existing antibiotics for infections caused by multiresistant Gram-negative bacteria and developing prophylactic vaccines.