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EmrAB-TolC Protein Complex in E. coli: Computational and Experimental Approaches

January 10, 2025
by Finley Heesch

 

Abstract: 

The CDC reports that over two million people in the United States alone become infected with antibiotic resistant bacteria. This paper studies one of the primary mechanisms of antibiotic resistance, efflux, in Escherichia coli. EmrA and EmrB proteins, belonging to the efflux pump EmrAB-TolC were purified in two types of competent cells to evaluate the methodology of the protein purification procedure. Analysis of each purified protein was completed using a variety of standard wet lab techniques. The structure of the complex was determined using artificial intelligence-based structure prediction software. This project presents effective methods for the purification of EmrAB and presents a model that reveals C9 homo-oligomeric arrangement of subunit EmrA in complex with a dimeric EmrB. Basic ligand binding assays were completed with known substrates in silico. Confirming protein purification methods allow future research to continue in vitro, with the eventual goal of experimentally determining the complex at a high resolution and aid in the future identification of drug targets and development of EmrAB-TolC protein inhibitors.

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