Related Experiment Video
Updated: Jun 3, 2026
07:31
Native Cell Membrane Nanoparticles System for Membrane Protein-Protein Interaction Analysis
Published on: July 16, 2020
Structural properties of a membrane associated anchor dipeptide.
Victor V Volkov1, Riccardo Chelli, Francesco Muniz-Miranda
1European Laboratory for Nonlinear Spectroscopy (LENS), Università di Firenze, Via Nello Carrara 1, I-50019 Sesto Fiorentino, Italy.
The Journal of Physical Chemistry. B
|March 30, 2011
Summary
N-myristoylated methyl glycine (MrG) peptides preferentially adopt an unfolded conformation when associating with phospholipid membranes. The anchor tail inserts into the hydrophobic region, aligning with lipid tails.
Area of Science:
- Biophysics
- Spectroscopy
- Computational Chemistry
Background:
- Peptide-membrane interactions are crucial for viral functions and drug delivery.
- Understanding how anchor peptides associate with lipid bilayers informs drug design and viral mechanisms.
Purpose of the Study:
- To investigate the association of an anchor dipeptide, N-myristoylated methyl glycine (MrG), with 1-palmitoyl-2-linoleyl phosphatidylcholine (PLPC) membranes.
- To determine the conformation and orientation of MrG within the phospholipid bilayer.
Main Methods:
- Two-dimensional infrared (2DIR) spectroscopy in the 6 μm region.
- Ab initio calculations.
- Replica exchange molecular dynamics (MD) simulations.
Main Results:
- MrG exhibits a preferential unfolded conformation (Φ = -90 ± 20°, Ψ = -180 ± 20°).
- Amide I transition dipole moments align with PLPC carbonyls at angles of 21-33°.
- The MrG anchor tail is fully inserted in the hydrophobic region, aligning with PLPC hydrocarbon tails.
Conclusions:
- MrG adopts a stable, extended conformation within the PLPC membrane.
- The findings provide insights into the molecular mechanisms of peptide-lipid interactions.
- This study contributes to understanding the behavior of membrane-associated peptides and anchor-containing molecules.
Related Concept Videos
01:32Lipids as Anchors
In the plasma membrane, the lipids forming the bilayer can also act as an anchor to tether proteins to the membrane. The three main types of lipid anchors found in eukaryotes are – prenyl groups, fatty acyl groups, and glycosylphosphatidylinositol or GPI groups. Prenyl and fatty acyl groups act as anchors on the cytosolic surface of the membrane, whereas GPI anchors proteins on the extracellular side.
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
01:29GPI Anchoring of Proteins in the ER Membrane
GPI-anchoring is a post-translational, reversible protein modification that is ubiquitous in eukaryotes. Such proteins are primarily present on the exoplasmic leaflet of the plasma membrane.
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
00:59Mechanisms of Membrane Domain Formation
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...
Another mechanism for membrane domain formation involves membrane proteins interacting with cytoskeletal...
01:09Multi-pass Transmembrane Proteins and β-barrels
In multi-pass transmembrane proteins, the polypeptide chain crosses the membrane more than once. The transmembrane polypeptide chain either forms an α-helix or β-strand structure. α-Helix containing multi-pass transmembrane proteins are ubiquitous, whereas β-strand containing ones are mainly found in gram-negative bacteria, mitochondria, and chloroplasts.
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...
01:45Tail-anchoring of Proteins in the ER Membrane
Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
02:43Peptide Bonds
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...