CLAMP · Deciphering Membrane Compartmentalization in Protein-Misfolding Bacterial Dysfunction to Re-Sensitize Multi-Drug Resistant Pathogens.

Multi-drug resistant (MDR) bacterial infections threaten all the advances in modern medicine after the industry nearly abandoned antibiotic development and no mechanism to suppress antibiotic resistance has been found. However, our results indicate that this mechanism does exist and is conserved in functional membrane microdomains (FMM) in all prokaryotes. We discovered bacterial FMM, akin to eukaryotic lipid rafts, and demonstrated their crucial role in preserving proteins correctly folded at no ATP cost. FMM are essential for pathogens survival during infections thus, FMM perturbation causes the bacterial proteome to collapse, particularly affecting heterologous proteins responsible for MDR. This leads to attenuated infections and additionally re-sensitizing MDR pathogens to antibiotics. Studying FMM will transform our understanding of cellular membrane organization and its connection to protein misfolding disorders. Accordingly, this proposal will undertake an ambitious molecular characterization of FMM and its impact on bacterial proteostasis, and we will apply this knowledge to bring closer to the clinic a battery of anti-FMM drugs that target FMM to reactivate antibiotics against MDR infections. To achieve this, a first structural goal will describe FMM molecular organization, how FMM operate to prevent protein misfolding, and the molecular principles driving the assembly of membrane microdomains in cells. Secondly, a functional goal will describe the mechanism of proteome stabilization independent of ATP and its crucial role in pathogenesis. Finally, an applied goal will be to implement anti-FMM drugs to eliminate MDR infections and re-sensitize them to conventional antibiotics. This proposal unveils a new frontier in understanding the cellular programs for membrane compartmentalization, their connection to protein-misfolding cellular dysfunction, and the possibility of applying this knowledge to revitalize classical antibiotics against MDR infections.