Laura Montecino Fernández defendió este trabajo para la obtención del Máster en Genética y Biología Celular

24 de junio de 2021

Colistin is a dose-dependent cationic antimicrobial belonging to the polymyxin family, whose target is the outer membrane of Gram-negative bacteria, specifically the lipopolysaccharide (LPS). The effect of this antibiotic is increasing the permeability of the membrane, causing the leakage of the cytoplasmic content and the death of the bacteria. Due to its adverse effects, its use was limited and became practically obsolete in human medicine, while in veterinary medicine it has been widely used for decades in infectious diseases caused by enterobacteria.
Few years ago, a horizontally transferable resistance gene was described, called mediated colistin resistance 1 (mcr-1), member of the family of phosphoethanolamine transferase enzymes, which ultimately achieve the addition of phosphoethanolamine to Lipid A of the bacterial membrane. With this modification, colistin sensitivity is avoided. Although it is currently known that there are genes of this family from mcr-1 to mcr-9, the mcr-1 gene is more
prevalent, and its epidemiology has evolved rapidly worldwide. For this reason, it became necessary to evaluate the risk of the dispersion of this resistance in different environments, by means of projects of genetic characterization and keeping a complete surveillance against this type of biological threats