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bioRxiv · 10.1101/2021.02.25.432940

An integrated multi-wavelength SCATTIRSTORM microscope combining TIRFM and IRM modalities for imaging cellulases and other processive enzymes

Nong, D.·Haviland, Z. K.·Vasquez Kuntz, K. O.·Tien, M.·Anderson, C. T.·Hancock, W. O.
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Abstract

We describe a multimodal SCATTIRSTORM microscope for visualizing processive enzymes moving on immobilized substrates. The instrument combines Interference Reflection Microscopy (IRM) with multi-wavelength Total Internal Reflectance Fluorescence Microscopy (TIRFM). The microscope can localize quantum dots with a precision of 2.8 nm at 100 frames/s, and was used to image the dynamics of the cellulase, Cel7a interacting surface-immobilized cellulose. The instrument, which was built with off-the-shelf components and controlled by custom software, is suitable for tracking other degradative enzymes such as collagenases, as well as motor proteins moving along immobilized tracks.

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Nong, D., Haviland, Z. K., Vasquez Kuntz, K. O., Tien, M., Anderson, C. T., Hancock, W. O.. 2021-02-25. An integrated multi-wavelength SCATTIRSTORM microscope combining TIRFM and IRM modalities for imaging cellulases and other processive enzymes. https://doi.org/10.1101/2021.02.25.432940

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