title: Capture of a single molecule in a nanocavity.
abstract: We describe a heptameric protein pore that has been engineered to accommodate two different cyclodextrin adapters simultaneously within the lumen of a transmembrane beta barrel. The volume between the adapters is a cavity of approximately 4400 cubic angstroms. Analysis of single-channel recordings reveals that individual charged organic molecules can be pulled into the cavity by an electrical potential. Once trapped, an organic molecule shuttles back and forth between the adapters for hundreds of milliseconds. Such self-assembling nanostructures are of interest for the fabrication of multianalyte sensors and could provide a means to control chemical reactions.
authors.affiliation: Department of Medical Biochemistry and Genetics, Texas A&M University System Health Science Center, College Station, TX 77843, USA.
authors.forename: L Q
authors.initials: LQ
authors.lastname: Gu
authors.forename: S
authors.initials: S
authors.lastname: Cheley
authors.forename: H
authors.initials: H
authors.lastname: Bayley
mesh_terms: D000218:Adamantane / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000378:metabolism; D001427:Bacterial Toxins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D003505:Cyclodextrins / Q000737:chemistry* / Q000378:metabolism; D003998:Dicarboxylic Acids / Q000737:chemistry* / Q000378:metabolism; D004553:Electric Conductivity; D006460:Hemolysin Proteins / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D008564:Membrane Potentials; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D011487:Protein Conformation; D015202:Protein Engineering; D013816:Thermodynamics; D047392:beta-Cyclodextrins
chemical_list: C421745:1,3-adamantanedicarboxylic acid; D001427:Bacterial Toxins; D003505:Cyclodextrins; D003998:Dicarboxylic Acids; D006460:Hemolysin Proteins; D047392:beta-Cyclodextrins; C421602:hepta-6-sulfato-beta-cyclodextrin; C021091:staphylococcal alpha-toxin; C102857:1-adamantanecarboxamide; C031215:betadex; D000218:Adamantane