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bioRxiv · 10.64898/2025.12.22.695957

Enhancing the imaging rate of high-speed atomic force microscopy using a combination of multiple techniques

Fukuda, S.·Otomo, A.·Iino, R.·Ando, T.
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Abstract

Protein molecules, while functioning, undergo dynamic conformational changes and interactions with their partners, which can be directly observed by high-speed atomic force microscopy (HS-AFM). However, its imaging rate of approximately 10 frames per second (fps) has remained unchanged since its inception, despite the increasing demand for observing dynamic biomolecular processes that occur too fast to be captured at this time resolution. Here we report a combination of techniques that significantly enhances the imaging rate without disturbing the sample. HS-AFM imaging of the stator ring of F1-ATPase visualised two intermediate states, which could not be resolved with the previous HS-AFM system. The high-resolution molecular movies demonstrate how the catalytic subunits cooperate during the chemomechanical cycle.

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Fukuda, S., Otomo, A., Iino, R., Ando, T.. 2025-12-24. Enhancing the imaging rate of high-speed atomic force microscopy using a combination of multiple techniques. https://doi.org/10.64898/2025.12.22.695957

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