Tether-supported biomembranes with α-helical peptide-based anchoring constructs

The strict requirement of constructing a native lipid environment to preserve the structure and functionality of membrane proteins is the starting constraint when building biomaterials and sensor systems from these biomolecules. To enhance the viability of supported biomembranes systems and build ne...

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Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 29(2013), 1 vom: 08. Jan., Seite 299-307
1. Verfasser: Zhong, Lina (VerfasserIn)
Weitere Verfasser: Tu, Raymond, Gilchrist, M Lane
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2013
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. Lipids Membrane Proteins Peptides Polyethylene Glycols 3WJQ0SDW1A Silicon Dioxide 7631-86-9
Beschreibung
Zusammenfassung:The strict requirement of constructing a native lipid environment to preserve the structure and functionality of membrane proteins is the starting constraint when building biomaterials and sensor systems from these biomolecules. To enhance the viability of supported biomembranes systems and build new ligand display interfaces, we apply rationally designed peptides partitioned into the lipid bilayer interface. Peptides designed to form membrane-spanning α-helical anchoring domains are synthesized using solid-phase peptide synthesis. K(3)A(4)L(2)A(7)L(2)A(3)K(2)-FITC is synthesized on the 100 mg scale for use as a biomembrane anchoring molecule, where orthogonal side-chain modifications allow us to introduce probes enabling peptide localization within supported bilayers. The peptides are found to form α-helical domains within liposomes as assessed with circular dichroism spectroscopy. These peptides are designed to be incorporated into lipid bilayers supported by microspheres and serve as biomembrane anchoring moieties to amino-terminated surfaces. Here, the silica bead surface (4.7 μm diameter) is activated with homobifunctional NHS-PEG(3000)-NHS as "polymer cushion" spacers. This tethering to a subset of the K(3)A(4)L(2)A(7)L(2)A(3)K(2)-FITC molecules present in the bilayer is achieved by the fusion of liposomes followed by coupling of the peptide amino groups to the NHS presented from the silica microsphere surfaces. The biomembrane distributions of tethered and untethered K(3)A(4)L(2)A(7)L(2)A(3)K(2)-FITC are probed with confocal microscopy and are found to give 3D reconstructions consistent with largely homogeneous supported biomembranes. The fluidity of the untethered fraction of peptides within supported membranes is quantified using the fluorescence recovery after photobleaching (FRAP) technique. The presence of the PEG(3000) polymer cushion facilitated a 28.9% increase in peptide diffusivity over untethered bilayers at the lowest peptide to lipid ratio we examined. We show that rationally designed peptide-based anchors can be used to tether lipid bilayers, creating a polymer-cushioned lipid microenvironment on surfaces with high lateral mobility and facilitating the development of a new platform for ligand displays
Beschreibung:Date Completed 14.06.2013
Date Revised 21.03.2024
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la303628n