High-Speed “4D” Computational Microscopy of Bacterial Surface Motility

ORAL

Abstract

Bacterial surface appendage-driven motility modes play key roles in early-stage biofilm community development. Examples include type IV pili-driven “twitching” and flagellum-driven “spinning” and “swarming” motilities controlled by molecular motors. Analysis of surface motility behavior is complicated by its inherently 3D nature, the speed of which is too fast for confocal microscopy to capture. Here, we combine electromagnetic field computation and statistical image analysis to generate 3D movies close to a surface at 5 ms time resolution using conventional inverted microscopes. Application of this technique on Pseudomonas aeruginosa, accompanied with hydrodynamic calculations, revealed that these tiny organisms act like spinning tops in the low Reynolds number regime. They undergo complex flagellum-driven dynamical behavior, including precession and nutation. We also observe an unexpected taxonomy of surface motility mechanisms, like horizontal bacteria that follow helicoidal trajectories and exhibit superdiffusive movements parallel to the surface. We further apply this technique to discern the effects on motility by each set of flagellum stators, MotAB and MotCD, in P. aeruginosa.

*J.d.A. [Eugene V. Cota-Robles Fellowship]. G.C.L.W [HFSP RGP0061/2013 and NIH R01AI102584].

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Presenters

  • Jaime De Anda

    • Department of Bioengineering, University of California - Los Angeles

Authors

  • Jaime De Anda

    • Department of Bioengineering, University of California - Los Angeles

  • Ernest Lee

    • Department of Bioengineering, University of California - Los Angeles
    • Bioengineering, University of California, Los Angeles

  • Calvin Lee

    • Department of Bioengineering, University of California - Los Angeles
    • Univ of California - Los Angeles

  • Rachel Bennett

    • Department of Physics, University of Pennsylvania

  • Xiang Ji

    • Department of Physics, University of California San Diego

  • Soheil Soltani

    • Department of Chemical Engineering and Materials Sciences, University of Southern California
    • Chem Eng and Materials Science, University of Southern California

  • Mark Harrison

    • Department of Chemical Engineering and Materials Sciences, University of Southern California

  • Amy Baker

    • Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth

  • Yun Luo

    • DuPont Industrial Biosciences

  • Thomas Chou

    • Department of Biomathematics and Mathematics, University of California Los Angeles
    • Univ of California - Los Angeles
    • Biomathematics, Mathematics, University of California, Los Angeles
    • Biomathematics, UCLA
    • Biomathematics, University of California, Los Angeles

  • George O'Toole

    • Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth

  • Andrea Armani

    • Department of Chemical Engineering and Materials Sciences, University of Southern California
    • Chem Eng and Materials Science, University of Southern California

  • Ramin Golestanian

    • Rudolf Peierls Center for Theoretical Physics, University of Oxford

  • Gerard Wong

    • Department of Bioengineering, University of California - Los Angeles
    • Univ of California - Los Angeles
    • Bioengineering, University of California, Los Angeles
    • Bioengineering, Chemistry, CNSI, UCLA