title: Translocation of double-stranded DNA through membrane-adapted phi29 motor protein nanopores.
abstract: Biological pores have been used to study the transport of DNA and other molecules, but most pores have channels that allow only the movement of small molecules and single-stranded DNA and RNA. The bacteriophage phi29 DNA-packaging motor, which allows double-stranded DNA to enter the virus during maturation and exit during an infection, contains a connector protein with a channel that is between 3.6 and 6 nm wide. Here we show that a modified version of this connector protein, when reconstituted into liposomes and inserted into planar lipid bilayers, allows the translocation of double-stranded DNA. The measured conductance of a single connector channel was 4.8 nS in 1 M KCl. This engineered and membrane-adapted phage connector is expected to have applications in microelectromechanical sensing, microreactors, gene delivery, drug loading and DNA sequencing.
authors.affiliation: Department of Biomedical Engineering, College of Engineering and College of Medicine, University of Cincinnati, Cincinnati, OH 45267, USA.
authors.forename: David
authors.initials: D
authors.lastname: Wendell
authors.forename: Peng
authors.initials: P
authors.lastname: Jing
authors.forename: Jia
authors.initials: J
authors.lastname: Geng
authors.forename: Varuni
authors.initials: V
authors.lastname: Subramaniam
authors.forename: Tae Jin
authors.initials: TJ
authors.lastname: Lee
authors.forename: Carlo
authors.initials: C
authors.lastname: Montemagno
authors.forename: Peixuan
authors.initials: P
authors.lastname: Guo
mesh_terms: D001435:Bacteriophages / Q000378:metabolism*; D001692:Biological Transport; D036022:Capsid Proteins / Q000737:chemistry / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D042003:DNA Packaging; D004279:DNA, Viral / Q000378:metabolism*; D015640:Ion Channel Gating; D008051:Lipid Bilayers / Q000378:metabolism*; D008081:Liposomes / Q000378:metabolism; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000378:metabolism*; D049329:Nanostructures / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D016062:Porosity
chemical_list: D036022:Capsid Proteins; D004279:DNA, Viral; D008051:Lipid Bilayers; D008081:Liposomes; D020409:Molecular Motor Proteins; C097975:portal protein, bacteriophage phi29; D004247:DNA