Related Experiment Video
Updated: Dec 9, 2025
06:24
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
6.7K
Collective headgroup conformational transition in twisted micellar superstructures.
Francesca Baldelli Bombelli1, Debora Berti1, Silvia Milani1
1Department of Chemistry and CSGI, University of Florence, Sesto Fiorentino, Florence, Italy. berti@csgi.unifi.it baglioni@csgi.unifi.it.
Soft Matter
|September 10, 2020
Summary
This study reveals that 1,2-dilauroyl-phosphatidyl-adenosine (DLPA) micelles exhibit distinct structures based on their thermal history. Warming DLPA micelles causes irreversible changes in their self-assembled structures due to adenosine headgroup conformation shifts.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Biophysical Chemistry
Background:
- Amphiphilic self-assembly design traditionally focuses on molecular shape and charge.
- Functional surfactants require advanced design strategies for responsive self-assemblies.
- 1,2-dilauroyl-phosphatidyl-adenosine (DLPA) is a functional amphiphile with adenosine headgroups.
Purpose of the Study:
- To comprehensively characterize the structural and spectroscopic properties of DLPA micelles.
- To investigate the influence of thermal history on DLPA micelle self-assembly.
- To elucidate the molecular mechanisms behind thermally induced structural changes.
Main Methods:
- Combined structural and spectroscopic characterization (NMR, CD, FTIR).
- Molecular dynamics (MD) simulations.
- Controlled temperature variation and sample aging protocols.
Main Results:
- DLPA micelles exist in at least two distinct structural states at room temperature, dependent on thermal history.
- Warming above 35 °C causes collapse of aged superstructures into aligned filaments or wormlike structures.
- These structural changes are irreversible upon cooling due to frozen adenosine headgroup conformations.
Conclusions:
- The thermal history critically dictates the self-assembled structure of DLPA micelles.
- Adenosine headgroup conformation plays a key role in the observed thermally induced structural transitions.
- DLPA self-assemblies exhibit a form of 'molecular memory' influenced by conformational dynamics.
More Related Videos
Related Concept Videos
01:22Protein Folding
125.3K
Overview
125.3K
01:25Protein Folding
10.5K
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
10.5K
00:52¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
1.1K
At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...
1.1K
00:59Mechanisms of Membrane Domain Formation
3.6K
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...
Another mechanism for membrane domain formation involves membrane proteins interacting with...
3.6K
02:11Conformations of Cyclohexane
14.8K
Cyclohexane does not exist in a planar form due to the high angle and torsional strain it would experience in the planar structure. Instead, it adopts non-planar chair and boat conformations.
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal...
14.8K
01:15Mechanisms of Membrane-bending
3.1K
The living membranes are flexible due to their fluid mosaic nature; however, their bending into different shapes is an active process regulated by specific lipids and proteins. The membrane bending can be transient as seen in vesicles or stable for a long time as in microvilli. Cells regulate the size, location, and duration of the membrane curvature.
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
3.1K