Mixed monolayers of gramicidin A (GA) and three alcohols, differing in the degree of fluorination, namely C18OH, F18OH, and F8H10OH have been investigated by means of: surface manometry (pi-A isotherms) and Brewster angle microscopy (BAM) aiming at finding appropriate molecules for incorporating gramicidin A for a biosensor design. Our results proved that only the semifluorinated alcohol is appropriate material for this purpose since it forms miscible and homogeneous monolayers with GA within the whole concentration range. The experimental results have been supported by the calculations of van der Waals energy profiles using the Insight II program. Both the hydrogenated and perfluorinated alcohols were found to aggregate at higher surface pressures, which exclude their application for gramicidin-based biosensor construction.
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http://dx.doi.org/10.1016/j.jcis.2007.04.060 | DOI Listing |
Biomolecules
December 2024
Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy Prospekt, 119071 Moscow, Russia.
Gramicidin A is a natural antimicrobial peptide produced by . Its transmembrane dimer is a cation-selective ion channel. The channel is characterized by the average lifetime of the conducting state and the monomer-dimer equilibrium constant.
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April 2025
Faculty of Chemistry, University of Warsaw, 1 Pasteur Street, 02-093 Warsaw, Poland. Electronic address:
Phys Rev E
June 2024
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31/4 Leninskiy prospekt, Moscow 119071, Russia.
Gramicidin A (gA) is a short hydrophobic β-helical peptide that forms cation-selective channels in lipid membranes in the course of transbilayer dimerization. The length of the gA helix is smaller than the thickness of a typical lipid monolayer. Consequently, elastic deformations of the membrane arise in the configurations of gA monomers, conducting dimer, and the intermediate state of coaxial pair, where gA monomers from opposing membrane monolayers are located one on top of the other.
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October 2024
IMEM-BRT Group, Departament d'Enginyeria Química, EEBE, Universitat Politècnica de Catalunya, C/ Eduard Maristany, 10-14, Ed. I, 2nd Floor, 08019 Barcelona, Spain; Barcelona Research Center in Multiscale Science and Engineering, EEBE, Universitat Politècnica de Catalunya, C/ Eduard Maristany, 10-14, Basement S-1, 08019 Barcelona, Spain. Electronic address:
The utilization of biomimetic membranes supported by advanced self-assembled monolayers is gaining attraction as a promising sensing tool. Biomimetic membranes offer exceptional biocompatibility and adsorption capacity upon degradation, transcending their role as mere research instruments to open new avenues in biosensing. This study focused on anchoring a sparsely tethered bilayer lipid membrane onto a self-assembled monolayer composed of a biodegradable polymer, functionalized with poly(ethylene glycol)-cholesterol moieties, for lipid membrane integration.
View Article and Find Full Text PDFBioengineering (Basel)
April 2024
Food & Energy Security Research & Product Centre, Sendai 980-0871, Japan.
We have investigated the morphology of two-dimensional monolayers of gramicidin-D (GD) and alamethicin (Al) formed on the water surface by the dropping method (DM) using surface tension measurement (STm), Brewster angle microscopy (BAM), and atomic force microscopy (AFM). Dynamic light scattering (DLS) revealed that GD in alcoholic solutions formed a dimeric helical structure. According to the CD and NMR spectroscopies, GD molecules existed in dimer form in methanol and lipid membrane environments.
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