High-speed Atomic Force Microscopy for Directly Visualizing Dynamic Biomolecular Processes
Abstract: We have developed high-speed AFM capable of directly visualizing dynamic processes played by protein molecules at high spatial and temporal resolution. It was achieved by increasing the response speed of all devices contained in AFM and by developing techniques for damping scanner vibrations and for reducing the tip-sample interaction force. Thereby, the imaging speed reached 40-70 ms/frame. Moreover, the high-speed imaging does not disturb delicate protein-protein interactions. Using this new microscopy, we succeed in directly imaging dynamic behaviors of functioning proteins. We also exemplified that the functional mechanisms of proteins can be elucidated straightforwardly from the dynamic imaging. In this review, we first mention our motivation of developing high-speed AFM, and then describe the outline of the instrument development, obtained dynamic images, and the future prospects of high-speed AFM.
Key words: AFM, imaging, proteins, dynamic processes, visualization