CAREER: Elucidating the biophysical mechanisms of membrane protein folding and stability through advanced single-molecule force spectroscopy

Membrane proteins are essential molecular machines that allow cells to interact with their environment, but we know surprisingly little about how they achieve and maintain their proper structure or “fold”. This research project will develop new methods to study these important proteins by probing them with applied mechanical force, one molecule at a time.

Although sophisticated physical analysis will be brought to bear, the basic idea is that stronger interactions in the protein will require more force to disrupt them. Results from experiments on multiple protein species and in carefully controlled chemical environments will improve fundamental biophysical understanding of membrane-protein structure formation and yield insights that could lead to new protein engineering strategies, better drug design, and new treatments for diseases caused by malfunctioning membrane proteins.

The project will also enhance science education by incorporating cutting-edge biophysics concepts into undergraduate and graduate courses while creating opportunities for students from diverse backgrounds to participate in research at the interface of chemistry, biology, and physics.

The research will use atomic force microscopy to measure the forces that hold membrane proteins in their functional, folded shapes, addressing fundamental questions that have been difficult to study using traditional biochemical methods. By precisely pulling on individual protein molecules, the project will determine how proteins interact with the cell membrane and maintain proper orientation, how different membrane environments affect protein structure, and how proteins achieve their final folded state during cellular synthesis.

New insights will emerge from new techniques, including advances in biological atomic force microscopy, chemical attachment methods, and ways to isolate and study proteins in their native membrane environment. The work will focus particularly on understanding how protein and lipid charge together control protein orientation in membranes, how the lipids of the membrane influence the structure of cellular signaling proteins, and how all of this is affected by interactions with other proteins that facilitate membrane protein folding.

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.