title: Optical Pushing: A Tool for Parallelized Biomolecule Manipulation.
abstract: The ability to measure and manipulate single molecules has greatly advanced the field of biophysics. Yet, the addition of more single-molecule tools that enable one to measure in a parallel fashion is important to diversify the questions that can be addressed. Here we present optical pushing (OP), a single-molecule technique that is used to exert forces on many individual biomolecules tethered to microspheres using a single collimated laser beam. Forces ranging from a few femtoNewtons to several picoNewtons can be applied with a submillisecond response time. To determine forces exerted on the tethered particles by the laser, we analyzed their measured Brownian motion using, to our knowledge, a newly derived analytical model and numerical simulations. In the model, Brownian rotation of the microspheres is taken into account, which proved to be a critical component to correctly determine the applied forces. We used our OP technique to map the energy landscape of the protein-induced looping dynamics of DNA. OP can be used to apply loading rates in the range of 10(-4)-10(6) pN/s to many molecules at the same time, which makes it a tool suitable for dynamic force spectroscopy.
authors.affiliation: Department of Physics and Astronomy and LaserLaB, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Gerrit
authors.initials: G
authors.lastname: Sitters
authors.affiliation: Department of Physics and Astronomy and LaserLaB, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Niels
authors.initials: N
authors.lastname: Laurens
authors.affiliation: Department of Physics and Astronomy and LaserLaB, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Emilie J
authors.initials: EJ
authors.lastname: de Rijk
authors.affiliation: Experimental Physics I, University of Bayreuth, Bayreuth, Germany; Department of Applied Physics, Eindhoven University of Technology, Eindhoven, The Netherlands.
authors.forename: Holger
authors.initials: H
authors.lastname: Kress
authors.affiliation: Department of Physics and Astronomy and LaserLaB, VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Erwin J G
authors.initials: EJ
authors.lastname: Peterman
authors.affiliation: Department of Physics and Astronomy and LaserLaB, VU University Amsterdam, Amsterdam, The Netherlands. Electronic address: g.j.l.wuite@vu.nl.
authors.forename: Gijs J L
authors.initials: GJ
authors.lastname: Wuite
mesh_terms: D001696:Biomechanical Phenomena; D004247:DNA / Q000378:metabolism; D007834:Lasers; D055595:Mechanical Phenomena; D008863:Microspheres; D036103:Nanotechnology / Q000379:methods*; D055620:Optical Phenomena; D017785:Photons; D011506:Proteins / Q000378:metabolism
chemical_list: D011506:Proteins; D004247:DNA