title: Channel-forming membrane proteins as molecular sensors.
abstract: Membrane channels are typically around or less than 1 nm in diameter and a description of the flow through them requires a molecular approach called nanofluidic. The ion current through channels is extremely sensitive to pore sizes. It is tempting to use the ion current to probe conformational changes of the channel or, for a fixed channel conformation, the current can be used to follow binding of molecules to the pore surfaces. Here we show the sensitivity of this method. It is possible to observe the passage of single isolated molecules through the channel and it is possible to discriminate between different passing molecules. Bioengineering allows us to modify channel surfaces and the affinity to different host molecules. Combining engineered proteins with the appropriated detection technique will allow a new type of molecular sensor.
authors.affiliation: IPBS-CNRS UMR5089, Toulouse F-31077, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Danelon
authors.forename: Marcus
authors.initials: M
authors.lastname: Lindemann
authors.forename: Christine
authors.initials: C
authors.lastname: Borin
authors.forename: Didier
authors.initials: D
authors.lastname: Fournier
authors.forename: Mathias
authors.initials: M
authors.lastname: Winterhalter
mesh_terms: D000667:Ampicillin / Q000737:chemistry; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000502:physiology*; D015374:Biosensing Techniques; D004594:Electrophysiology; D004926:Escherichia coli; D007473:Ion Channels / Q000737:chemistry / Q000502:physiology*; D044085:Microfluidics / Q000379:methods*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D007473:Ion Channels; D000667:Ampicillin