Grant: CIHR Fellowship

The rapid rise of antibiotic resistance in pathogenic gram-negative bacteria represents an emerging public health crisis. Bacterial infections by these multi-drug resistant organisms are difficult to treat because of their high intrinsic resistance against many clinically useful antibiotics. Species of particular concern include members of the Pseudomonas, Acinetobacter, Klebsiella and Burkholderia genera, whose resistance towards many standard antibiotic treatments are well-documented. The opportunistic pathogen Burkholderia cenocepacia is of particular concern for immune compromised individuals, particularly cystic fibrosis patients - B. cenocepacia infection can lead to respiratory failure and premature death. Antibiotic resistance in B. cenocepacia is partially dependent on the contents of its protective cell wall. A critical step in cell wall synthesis is performed by a membrane protein, ArnT. Notably, the activity of the ArnT protein is known to be important for cell wall biogenesis across multiple different strains of pathogenic bacteria - underscoring its importance in bacterial pathogenicity. However, many aspects of its mechanism of action remain uncharacterized. The goal of this research proposal is to apply the latest advances in native mass spectrometry - a powerful emerging technology for characterizing membrane proteins in precise detail - towards studying the function and regulation of B. cenocepacia ArnT. I will apply native mass spectrometry, along with other complementary membrane protein biochemistry techniques, to characterize the biological activity of ArnT. This information will shed valuable light on its mechanism of action and will hopefully lead to the discovery of new therapeutic drugs which can inhibit the activity of ArnT, thus reducing the virulence of pathogenic bacteria.