title: Molecular resolution visualization of a pore formed by trichogin, an antimicrobial peptide, in a phospholipid matrix.
abstract: Electrochemical scanning tunneling microscopy (EC-STM) was employed to study the aggregation of trichogin OMe (TCG), an antimicrobial peptide, incorporated into a lipid monolayer. High-resolution EC-STM images show that trichogin molecules aggregate to form channels in the lipid monolayer. Two types of aggregates were observed in the images. The first consisted of a bundle of six TCG molecules surrounding a central pore. The structure and dimensions of this channel are similar to aggregates that in bilayers are described by the barrel-stave model. The EC-STM images also reveal that channels aggregate further to form a hexagonal lattice of a two dimensional (2D) nanocrystal. The model of 2D lattice was built from trimers of TCG molecules that alternatingly are oriented with either hydrophilic or hydrophobic faces to each other. In this way each TCG molecule is oriented partially with its hydrophilic face towards the hexameric pore allowing the formation of the column of water inside this pore.
authors.affiliation: Department of Chemistry, University of Guelph, Guelph, ON N1G 2W1, Canada.
authors.forename: Maxim
authors.initials: M
authors.lastname: Smetanin
authors.affiliation: Department of Chemistry, University of Guelph, Guelph, ON N1G 2W1, Canada; Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Zwirki i Wigury 101, 02-089 Warsaw, Poland.
authors.forename: Slawomir
authors.initials: S
authors.lastname: Sek
authors.affiliation: Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy.
authors.forename: Flavio
authors.initials: F
authors.lastname: Maran
authors.affiliation: Department of Chemistry, University of Guelph, Guelph, ON N1G 2W1, Canada. Electronic address: jlipkows@uoguelph.ca.
authors.forename: Jacek
authors.initials: J
authors.lastname: Lipkowski
keywords: Antimicrobial peptide; Barrel-stave model; Peptide aggregation; Scanning tunneling microscopy; Trichogin