title: Dynamics of unfolded protein transport through an aerolysin pore.
abstract: Protein export is an essential mechanism in living cells and exported proteins are usually translocated through a protein-conducting channel in an unfolded state. Here we analyze, by electrical detection, the entry and transport of unfolded proteins, at the single molecule level, with different stabilities through an aerolysin pore, as a function of the applied voltage and protein concentration. The frequency of ionic current blockades varies exponentially as a function of the applied voltage and linearly as a function of protein concentration. The transport time of unfolded proteins decreases exponentially when the applied voltage increases. We prove that the ionic current blockade duration of a double-sized protein is longer than that assessed for a single protein supporting the transport phenomenon. Our results fit with the theory of confined polyelectrolyte and with some experimental results about DNA or synthetic polyelectrolyte translocation through protein channels as a function of applied voltage. We discuss the potential of the aerolysin nanopore as a tool for protein folding studies as it has already been done for α-hemolysin.
authors.affiliation: Equipe Matériaux Polymères aux Interfaces, CNRS-UMR 8587, LAMBE, Université d'Évry, Bd F. Mitterrand, 91025 Évry France.
authors.forename: Manuela
authors.initials: M
authors.lastname: Pastoriza-Gallego
authors.forename: Leila
authors.initials: L
authors.lastname: Rabah
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gibrat
authors.forename: Bénédicte
authors.initials: B
authors.lastname: Thiebot
authors.forename: Françoise Gisou
authors.initials: FG
authors.lastname: van der Goot
authors.forename: Loïc
authors.initials: L
authors.lastname: Auvray
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Betton
authors.forename: Juan
authors.initials: J
authors.lastname: Pelta
mesh_terms: D001427:Bacterial Toxins / Q000378:metabolism*; D004560:Electricity; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D033902:Periplasmic Binding Proteins / Q000235:genetics / Q000378:metabolism*; D052899:Pore Forming Cytotoxic Proteins / Q000378:metabolism*; D021381:Protein Transport; D058767:Protein Unfolding; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D001427:Bacterial Toxins; D029968:Escherichia coli Proteins; C461619:MalE protein, E coli; D033902:Periplasmic Binding Proteins; D052899:Pore Forming Cytotoxic Proteins; D011994:Recombinant Proteins; C032676:aerolysin