Porin of Pseudomonas aeruginosa forms low conductance ion channel in planar lipid bilayers

Biochem Biophys Res Commun. 1992 Jul 31;186(2):645-51. doi: 10.1016/0006-291x(92)90795-m.

Abstract

Protein E1, a porin of the outer membrane of Pseudomonas aeruginosa, was reconstituted into planar lipid bilayers. Single channel conductance of the protein appeared to be 230 pS (pico siemens) in 1 M KCl-10 mM Hepes, pH7.2. This value is approximately 5 times lower than the conductance of the OmpF channel of Escherichia coli. Conductance increased linearly as the membrane potential was raised from -200 mV to +200 mV, and was nearly proportional to the KCl concentration. These results show that protein E1 is probably a genuine porin in the P. aeruginosa outer membrane supporting the earlier conclusion that protein E1 forms a small channel.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Outer Membrane Proteins / isolation & purification
  • Bacterial Outer Membrane Proteins / metabolism*
  • Cell Membrane / physiology
  • Electric Conductivity
  • Escherichia coli / physiology
  • Ion Channels / physiology*
  • Kinetics
  • Lipid Bilayers*
  • Membrane Potentials
  • Molecular Weight
  • Porins
  • Pseudomonas aeruginosa / physiology*

Substances

  • Bacterial Outer Membrane Proteins
  • Ion Channels
  • Lipid Bilayers
  • Porins