Probing ion channel conformational dynamics using simultaneous single-molecule ultrafast spectroscopy and patch-clamp electric recording

Harms, Greg; Orr, Galya; Lu, H. Peter
March 2004
Applied Physics Letters;3/8/2004, Vol. 84 Issue 10, p1792
Academic Journal
An approach to probing single-molecule ion channel kinetics and conformational dynamics, patch-clamp confocal fluorescence microscopy (PCCFM), uses simultaneous ultrafast fluorescence spectroscopy and single-channel electric current recording. PCCFM is applied to determine single-channel conformational dynamics by probing single-pair fluorescence resonant energy transfer, fluorescence self-quenching, and anisotropy of the dye-labeled gramicidin ion channel incorporated in an artificial lipid bilayer. Hidden conformational changes were observed, which strongly suggests that multiple intermediate conformation states are involved in gramicidin ion channel dynamics. © 2004 American Institute of Physics.


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