Functional dynamics of essential bacterial proteins and EPR technology development

Project Summary/Abstract Proteins are vital to all biological processes, driving cellular functions and dysfunctions that directly affect human health. Detailed knowledge of protein structure and dynamics is critical to understanding their function so that effective and directed therapeutics can be developed to improve human health. For example, society is in dire need of novel antibiotics against drug-resistant bacteria. This proposal integrates my expertise in and current research on protein structure and functional dynamics related to antibiotic resistance in Gram-negative and Gram-positive bacteria and the development of transformative electron paramagnetic resonance (EPR) spectroscopy technologies for biomedically relevant structural biology applications. The lipopolysaccharide (LPS) transport (Lpt) system of Gram-negative bacteria features tempting new drug targets against important pathogens such as Escherichia coli, Salmonella typhimurium, and Vibrio cholera. The periplasmic structures of the Lpt proteins are particularly attractive as potential antibiotic targets due to their critical role in the essential LPS transport process, their unique structural fold (no mammalian proteins have yet been identified as having this fold; thus, drugs aimed at this structure would be specific and effective antibiotics against Gram-negative pathogens), and their need to dock with each other at structurally homologous interfaces (drugs disrupting these unique protein-protein interactions result in cell death). Similarly, a better understanding of antibiotic-resistant enterococci such as Enterococcus faecalis, which are intestinal microbes that normally coexist within their host yet are one of the most common causes of hospital-acquired infections after treatment with antibiotics such as cephalosporins, is critical to developing novel strategies to prevent or treat multidrug-resistant enterococci. Furthermore, development of advanced instrumentation technologies such as EPR spectroscopy that are ideally suited to the study of detailed representations of protein structure and functional dynamics is essential to understanding protein function across the entire scope of human health and disease.