The overall scientific goal of the research undertaken in Prof Brown's laboratory is to determine the complex mechanisms used by bacteria to evade strategies employed by the host for their elimination, including the use of antimicrobial agents. Drug-resistant microorganisms are a major worldwide health issue as a number of important human pathogens have now acquired mechanisms that make them largely resistant to all currently available treatment regimes. One of the most significant resistance mechanisms involves membrane-bound efflux pumps that actively transport toxic antimicrobial compounds from the bacterial cell before they reach their intracellular target. Although many export systems transport a single substrate, or a small group of structurally-related substrates, a number of multidrug resistance (MDR) export systems are involved in the efflux of a wide range of structurally-dissimilar antimicrobial compounds. These MDR pumps are widespread amongst pathogenic bacteria and fungi, parasitic protozoa, and human tumour cells. With her team she is investigating the molecular structures, mechanistic processes and molecular evolution of these efflux pumps. Together with international collaborators, they have provided insights into the controversy of how proteins bind multiple ligands.

Additionally, we have recently developed a range of molecular techniques and model systems to analyse how the bacterium Acinetobacter baumannii has developed into such a successful pathogen.