title: Stiff filamentous virus translocations through solid-state nanopores.
abstract: The ionic conductance through a nanometer-sized pore in a membrane changes when a biopolymer slides through it, making nanopores sensitive to single molecules in solution. Their possible use for sequencing has motivated numerous studies on how DNA, a semi-flexible polymer, translocates nanopores. Here we study voltage-driven dynamics of the stiff filamentous virus fd with experiments and simulations to investigate the basic physics of polymer translocations. We find that the electric field distribution aligns an approaching fd with the nanopore, promoting its capture, but it also pulls fd sideways against the membrane after failed translocation attempts until thermal fluctuations reorient the virus for translocation. fd is too stiff to translocate in folded configurations. It therefore translocates linearly, exhibiting a voltage-independent mobility and obeying first-passage-time statistics. Surprisingly, lengthwise Brownian motion only partially accounts for the translocation velocity fluctuations. We also observe a voltage-dependent contribution whose origin is only partially determined.
authors.affiliation: Brown University, Department of Physics, Providence, Rhode Island 02912, USA.
authors.forename: Angus
authors.initials: A
authors.lastname: McMullen
authors.affiliation: University of Ontario Institute of Technology, Faculty of Science, Oshawa, Ontario, Canada L1H 7K4.
authors.forename: Hendrick W
authors.initials: HW
authors.lastname: de Haan
authors.affiliation: Brown University, Department of Physics, Providence, Rhode Island 02912, USA.
authors.forename: Jay X
authors.initials: JX
authors.lastname: Tang
authors.affiliation: Brown University, Department of Physics, Providence, Rhode Island 02912, USA.
authors.forename: Derek
authors.initials: D
authors.lastname: Stein
mesh_terms: D001435:Bacteriophages / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D001692:Biological Transport; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D058608:Nanopores / Q000648:ultrastructure; D049329:Nanostructures / Q000737:chemistry / Q000821:virology*; D011108:Polymers / Q000737:chemistry*
chemical_list: D004279:DNA, Viral; D011108:Polymers