Related Experiment Video
Updated: Mar 9, 2026
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
8.5K
Transient Helicity: Fuel-Driven Temporal Control over Conformational Switching in a Supramolecular Polymer
Shikha Dhiman1, Ankit Jain1, Subi J George1
1Supramolecular Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore, 560064, India.
Angewandte Chemie (International Ed. in English)
|December 30, 2016
Summary
This study introduces a synthetic supramolecular system that mimics biological systems by changing its helical structure using adenosine triphosphate (ATP) as fuel. This active system demonstrates controllable, transient helical conformations.
Area of Science:
- Supramolecular Chemistry
- Chirality
- Biomimetic Systems
Background:
- Synthetic supramolecular chirality often mimics natural systems.
- Biological conformational changes are dissipative, but synthetic non-equilibrium systems remain underdeveloped.
Purpose of the Study:
- To establish a synthetic supramolecular system capable of conformational changes under non-equilibrium conditions.
- To develop an active synthetic system utilizing a biologically relevant chemical fuel.
Main Methods:
- Development of a synthetic supramolecular system.
- Utilized adenosine triphosphate (ATP) as a chemical fuel source.
- Employed tandem enzyme catalysis to control conformational dynamics.
Main Results:
- Demonstrated temporal changes in helical conformation within the synthetic system.
- Achieved active conformational changes powered by ATP.
- Showcased transient and switchable helices with tunable lifetimes and stereomutation rates.
Conclusions:
- Successfully created a synthetic supramolecular system exhibiting active, ATP-driven conformational changes.
- The system provides a novel platform for studying non-equilibrium dynamics in synthetic chiral matter.
- Enzyme-mediated control offers modularity in helix lifetime and stereomutation.
Related Concept Videos
00:52¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
1.4K
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...
1.4K
00:57Cationic Chain-Growth Polymerization: Mechanism
3.0K
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...
3.0K
01:26Polymer Classification: Stereospecificity
3.4K
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
3.4K
01:15¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
1.8K
The axial and equatorial protons in cyclohexane can be distinguished by performing a variable-temperature NMR experiment. In this process, except for one proton, the remaining eleven protons are replaced by deuterium. The deuterium substitution avoids the possible peak splitting caused by the spin-spin coupling between the adjacent protons. The remaining proton flips between the axial and equatorial positions.
1.8K
01:21Polymer Classification: Crystallinity
4.2K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
4.2K
01:58Cooperative Allosteric Transitions
9.2K
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
9.2K