title: Ion channel formation by N-terminal domain: a common feature of OprFs of Pseudomonas and OmpA of Escherichia coli.
abstract: The proteolytic fragments of OprFs of Pseudomonas aeruginosa and Pseudomonas fluorescens were identified, respectively, as the first 175 and 177 amino acids from the N-terminal domain. They induced ion channels after reincorporation into planar lipid bilayers (85 and 75 pS, respectively, in 1 M NaCl). A similar conductance value (72 pS) was found for the eight beta-strand OmpA N-terminal domain (OmpA171) of Escherichia coli. We conclude that the N-terminal domain of OprFs is sufficient to induce ion channels and the comparison with OmpA171, provides strong evidence of the existence of an eight-stranded beta-barrel in the N-terminal domain of OprFs.
authors.affiliation: UMR 6522 CNRS,Faculté des Sciences, Mont-Saint-Aignan, France. nathalie.saint@univ-rouen.fr
authors.forename: N
authors.initials: N
authors.lastname: Saint
authors.forename: C
authors.initials: C
authors.lastname: El Hamel
authors.forename: E
authors.initials: E
authors.lastname: Dé
authors.forename: G
authors.initials: G
authors.lastname: Molle
mesh_terms: D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D007473:Ion Channels / Q000378:metabolism*; D008051:Lipid Bilayers; D008969:Molecular Sequence Data; D018272:Porins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011549:Pseudomonas / Q000235:genetics / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001425:Bacterial Outer Membrane Proteins; D007473:Ion Channels; D008051:Lipid Bilayers; D018272:Porins; C078167:OMPA outer membrane proteins