Modified reconstitution method used in patch-clamp studies of Escherichia coli ion channels

Biophys J. 1989 Sep;56(3):631-6. doi: 10.1016/S0006-3495(89)82710-9.

Abstract

We have modified the procedure of Criado and Keller (1987) to study ion channels of Escherichia coli reconstituted in liposomes. The modifications include (a) excluding the use of any detergent and (b) inducing blisters from liposomes with Mg2+. These blisters, which appear to be unilamellar, are stable for hours. They could be repeatedly sampled with different patch-clamp pipettes each achieving seal resistance greater than 10 GOhms. Activities of three types of ion channels are often observed by use of this method, including two voltage-sensitive cation channels of different conductances. Even the mechanosensitive channel, previously recorded from live E. coli cells (Martinac et al., 1987), was also detected in these blisters. Apparently the channel protein and any accessory structures, postulated to be needed for mechanotransduction, can be reconstituted together by this method.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cell Membrane / ultrastructure
  • Electrophysiology
  • Escherichia coli / metabolism*
  • Escherichia coli / ultrastructure
  • Ion Channels / metabolism*
  • Liposomes

Substances

  • Ion Channels
  • Liposomes