title: Direct observation of kinesin stepping by optical trapping interferometry.
abstract: Do biological motors move with regular steps? To address this question, we constructed instrumentation with the spatial and temporal sensitivity to resolve movement on a molecular scale. We deposited silica beads carrying single molecules of the motor protein kinesin on microtubules using optical tweezers and analysed their motion under controlled loads by interferometry. We find that kinesin moves with 8-nm steps.
authors.affiliation: Rowland Institute for Science, Cambridge, Massachusetts 02142.
authors.forename: K
authors.initials: K
authors.lastname: Svoboda
authors.forename: C F
authors.initials: CF
authors.lastname: Schmidt
authors.forename: B J
authors.initials: BJ
authors.lastname: Schnapp
authors.forename: S M
authors.initials: SM
authors.lastname: Block
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology; D000818:Animals; D002417:Cattle; D049832:Decapodiformes; D007368:Interferometry; D016547:Kinesins / Q000502:physiology*; D007834:Lasers; D008027:Light; D008863:Microspheres; D008870:Microtubules / Q000502:physiology; D009068:Movement / Q000502:physiology; D012822:Silicon Dioxide
chemical_list: D012822:Silicon Dioxide; D000255:Adenosine Triphosphate; D016547:Kinesins