title: Intrinsic rectification of ion flux in alamethicin channels: studies with an alamethicin dimer.
abstract: Covalent dimers of alamethicin form conducting structures with gating properties that permit measurement of current-voltage (I-V) relationships during the lifetime of a single channel. These I-V curves demonstrate that the alamethicin channel is a rectifier that passes current preferentially, with voltages of the same sign as that of the voltage that induced opening of the channel. The degree of rectification depends on the salt concentration; single-channel I-V relationships become almost linear in 3 M potassium chloride. These properties may be qualitatively understood by using Poisson-Nernst-Planck theory and a modeled structure of the alamethicin pore.
authors.affiliation: Department of Chemistry, University of Toronto, Canada. awoolley@chem.utoronto.ca
authors.forename: G A
authors.initials: GA
authors.lastname: Woolley
authors.forename: P C
authors.initials: PC
authors.lastname: Biggin
authors.forename: A
authors.initials: A
authors.lastname: Schultz
authors.forename: L
authors.initials: L
authors.lastname: Lien
authors.forename: D C
authors.initials: DC
authors.lastname: Jaikaran
authors.forename: J
authors.initials: J
authors.lastname: Breed
authors.forename: K
authors.initials: K
authors.lastname: Crowhurst
authors.forename: M S
authors.initials: MS
authors.lastname: Sansom
mesh_terms: D000408:Alamethicin / Q000737:chemistry*; D000595:Amino Acid Sequence; D019281:Dimerization; D015640:Ion Channel Gating; D007700:Kinetics; D008051:Lipid Bilayers; D008564:Membrane Potentials; D008954:Models, Biological; D008961:Models, Structural; D008969:Molecular Sequence Data; D010713:Phosphatidylcholines; D015221:Potassium Channels / Q000737:chemistry* / Q000502:physiology*; D011189:Potassium Chloride; D017433:Protein Structure, Secondary; D055672:Static Electricity; D013816:Thermodynamics
chemical_list: D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D015221:Potassium Channels; D000408:Alamethicin; C021016:1,2-diphytanoylphosphatidylcholine; D011189:Potassium Chloride