NSF Award
2305834
With the support of the Chemistry of Life Processes Program, Professor Gary A. Lorigan from the Miami University is studying two membrane proteins, namely pinholin and gp28, which are involved in cell lysis/cell death. Membrane proteins make up approximately one-third of all known proteins and are responsible for many important properties and functions of biological systems. Despite their abundance and importance, there is very little information about membrane-associated molecules. This project will apply electron paramagnetic resonance (EPR) spectroscopic techniques to gather information about the structural and dynamic properties of the membrane proteins pinholin and gp28. In the implementation of this project, graduate students and undergraduate student will acquire knowledge and experience in the preparation of membrane protein samples and in state-of-the-art EPR spectroscopic techniques. Undergraduate students will obtain valuable experience in biophysical chemistry and graduate students participation in DUOS, a STEM (science, technology, engineering and mathematics) project at Miami University, is an opportunity for them to become outstanding mentors.<br/><br/>Pinholin is a biologically significant membrane-bound holin protein that is directly involved in cell death through lysis of the inner membrane in E. coli. The other prinicipal target of these studies is gp28, a new type of protein that disrupts the outer membrane (OM) in phage phiKT. Currently, there is very limited structural information on both pinholin and gp28. The secondary and tertiary structure of mutated pinholin embedded in a lipid bilayer will be elucidated by measuring distances between strategically placed nitroxide spin labels using EPR spectroscopy. State-of-the-art EPR techniques such as double electron electron resonance (DEER) will be applied to study the structure, topology, oligomerization state, and dynamic properties of the membrane-bound proteins pinholin and gp28. Different conformational forms will be investigated. The EPR data will be used in the development of a structural model to help elucidate the mechanism of hole formation.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
