title: Placement of oppositely charged aminoacids at a polypeptide termini determines the voltage-controlled braking of polymer transport through nanometer-scale pores.
abstract: Protein and solid-state nanometer-scale pores are being developed for the detection, analysis, and manipulation of single molecules. In the simplest embodiment, the entry of a molecule into a nanopore causes a reduction in the latter's ionic conductance. The ionic current blockade depth and residence time have been shown to provide detailed information on the size, adsorbed charge, and other properties of molecules. Here we describe the use of the nanopore formed by Staphylococcus aureus α-hemolysin and polypeptides with oppositely charged segments at the N- and C-termini to increase both the polypeptide capture rate and mean residence time of them in the pore, regardless of the polarity of the applied electrostatic potential. The technique provides the means to improve the signal to noise of single molecule nanopore-based measurements.
authors.affiliation: Department of Interdisciplinary Research, Alexandru I. Cuza University, Iasi, Romania.
authors.forename: Alina
authors.initials: A
authors.lastname: Asandei
authors.affiliation: Center for Life Nano Science, Istituto Italiano di Tecnologia, Rome, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Chinappi
authors.affiliation: Research Center for Proteineous Materials, Chosun University, Gwangju, South Korea.
authors.forename: Jong-Kook
authors.initials: JK
authors.lastname: Lee
authors.affiliation: Department of Bioinformatics, Kongju National University, Kongju, South Korea.
authors.forename: Chang
authors.initials: C
authors.lastname: Ho Seo
authors.affiliation: Department of Physics, Alexandru I. Cuza University, Iasi, Romania.
authors.forename: Loredana
authors.initials: L
authors.lastname: Mereuta
authors.affiliation: Research Center for Proteineous Materials, Chosun University, Gwangju, South Korea.
authors.forename: Yoonkyung
authors.initials: Y
authors.lastname: Park
authors.affiliation: Department of Physics, Alexandru I. Cuza University, Iasi, Romania.
authors.forename: Tudor
authors.initials: T
authors.lastname: Luchian
mesh_terms: D000465:Algorithms; D000596:Amino Acids / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000737:chemistry; D007700:Kinetics; D008962:Models, Theoretical; D058608:Nanopores; D049329:Nanostructures; D036103:Nanotechnology; D010455:Peptides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013211:Staphylococcus aureus
chemical_list: D000596:Amino Acids; D006460:Hemolysin Proteins; D010455:Peptides; D011108:Polymers