Mechanisms of Antibiotic Recalcitrance in ESKAPE pathogens

ended

Antimicrobial resistance (AMR) is the silent pandemic uprising for the past decades that challenges practitioners to everyday life. In this context, more and more infections have become harder to treat, even in absence of genetic markers for AMR. This phenomenon, called recalcitrance, is related to the ability of susceptible bacteria to overcome antibiotic treatment and to reinitiate infection contributing to antibiotic failures and resistance emergence. Previous studies have described the involvement of a phenotypic switch leading to recalcitrance but underlying mechanism remain poorly understood. ESKAPE (standing for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) pathogens are the most prevalent causative agents in common recurrent healthcare-associated infections as well as well-known for their multidrug resistant phenotype and are the best candidates to understand recalcitrance. Hereby, we propose to investigate two of them, E. faecium (Efm) and E. cloacae complex (Ecc) by studying the proteome involved in recalcitrance. To identify any protein and/or pathway of interest, we will (i) identify which stress and bactericidal antibiotic induce recalcitrance both in Efm and Ecc; (ii) evaluate proteome and phosphoproteome of isolated antibiotic-recalcitrant bacteria; and (iii) confirm functionality of candidate proteins/pathways by mutagenesis and phenotypic approaches (in vitro and in cellulo) with the expertise of Prof. Helaine at Harvard Medical School (HMS) in Boston (secondment). Finding potential protein targets can highlight new candidates to further develop new therapies to overcome the rising of AMR.