Integrated multi-wavelength microscope combining TIRFM and IRM modalities for imaging cellulases and other processive enzymes

Nong, Daguan; Haviland, Zachary K.; Kuntz, Kate Vasquez; Tien, Ming; Anderson, Charles T. (ORCID:0000000174813571); Hancock, William O. (ORCID:0000000155478755)

doi:10.1364/boe.423798

DOE OSTI · 1842364

Integrated multi-wavelength microscope combining TIRFM and IRM modalities for imaging cellulases and other processive enzymes

Nong, Daguan·Haviland, Zachary K.·Kuntz, Kate Vasquez·Tien, Ming·Anderson, Charles T. (ORCID:0000000174813571)·Hancock, William O. (ORCID:0000000155478755)

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Abstract

We describe a multimodal 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 with surface-immobilized cellulose. The instrument, which was built with off-the-shelf components and is 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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09 BIOMASS FUELS 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY 47 OTHER INSTRUMENTATION 59 BASIC BIOLOGICAL SCIENCES biochemistry medical imaging molecular biology optics radiology, nuclear medicine

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Nong, Daguan, Haviland, Zachary K., Kuntz, Kate Vasquez, Tien, Ming, Anderson, Charles T. (ORCID:0000000174813571), Hancock, William O. (ORCID:0000000155478755). 2021-05-11. Integrated multi-wavelength microscope combining TIRFM and IRM modalities for imaging cellulases and other processive enzymes. https://doi.org/10.1364/boe.423798

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