title: Channel-sizing experiments in multichannel bilayers.
abstract: The possibility of obtaining information about the radius of high and low conductance states of channels in multichannel membranes was tested experimentally. In spite of the interference of non-electrolytes on the numbers of channels that appeared in the membrane, the non-electrolyte-exclusion method was successfully adapted to multichannel bilayers to estimate the radius of the larger opening of the low conductance state of the channel induced by Staphylococcus aureus alpha-toxin. At the pH used, the channel transition to a low conductance state was accompanied by a decrease of the opening radius from 1.3 +/- 0.2 nm to 0.9 +/- 0.1 nm. The determination criteria for maximum size of a channel opening when using the non-electrolyte exclusion method is discussed.
authors: Laboratory of Molecular Physiology, Institute of Physiology and Biophysics, Tashkent, Uzbekistan. kras@npd.ufpe.br
authors: O V
authors: OV
authors: Krasilnikov
authors: P G
authors: PG
authors: Merzlyak
authors: L N
authors: LN
authors: Yuldasheva
authors: R A
authors: RA
authors: Nogueira
mesh_terms: D004573:Electrolytes / Q000378:metabolism; D004594:Electrophysiology / Q000379:methods; D007473:Ion Channels / Q000502:physiology*; D013211:Staphylococcus aureus; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D004573:Electrolytes; D007473:Ion Channels; D010738:Type C Phospholipases