title: Porin of Pseudomonas aeruginosa forms low conductance ion channel in planar lipid bilayers.
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.
authors.affiliation: Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Obara
authors.forename: T
authors.initials: T
authors.lastname: Nakae
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002462:Cell Membrane / Q000502:physiology; D004553:Electric Conductivity; D004926:Escherichia coli / Q000502:physiology; D007473:Ion Channels / Q000502:physiology*; D007700:Kinetics; D008051:Lipid Bilayers; D008564:Membrane Potentials; D008970:Molecular Weight; D018272:Porins; D011550:Pseudomonas aeruginosa / Q000502:physiology*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D007473:Ion Channels; D008051:Lipid Bilayers; D018272:Porins