Related Experiment Video
Updated: Jun 11, 2025
07:54
Analysis of AtHIRD11 Intrinsic Disorder and Binding Towards Metal Ions by Capillary Gel Electrophoresis and Affinity Capillary Electrophoresis
Published on: August 22, 2018
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End Group Effects on Anion Binding in Tetraglycine Peptide: A Computational Study
Monalisha Sarma1, Manash Pratim Sarmah1, Manabendra Sarma1
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
Chemistry, an Asian Journal
|October 6, 2024
Summary
Tetraglycine peptides effectively bind phosphate and bisulfate anions through noncovalent interactions. Peptide modifications alter binding sites, offering insights for designing novel anion receptors in supramolecular chemistry.
Area of Science:
- Supramolecular Chemistry
- Computational Chemistry
- Biophysical Chemistry
Background:
- Anions play critical roles in biological and chemical processes.
- Developing selective anion receptors is crucial for various applications.
- Peptides offer a versatile platform for molecular recognition.
Purpose of the Study:
- To investigate tetraglycine peptides as receptors for dihydrogen phosphate (H2PO4-) and bisulfate (HSO4-) anions.
- To explore the influence of peptide form (zwitterionic, neutral, capped) on anion binding.
- To elucidate the molecular recognition mechanisms governing these host-guest interactions.
Main Methods:
- Molecular Dynamics (MD) simulations to determine complex conformations.
- Density Functional Theory (DFT) to quantify interaction energies.
- Quantum Mechanics/Molecular Mechanics (QM/MM) for proton transfer analysis.
- Symmetry-Adapted Perturbation Theory (SAPT) and noncovalent interaction analysis.
Main Results:
- Tetraglycine peptides bind H2PO4- and HSO4- via hydrogen bonding (N-H···O, O-H···O=C).
- Proton transfer in zwitterionic complexes alters peptide charge and binding site.
- End-group capping shifts anion binding from the backbone to the N-terminus.
- Electrostatic interactions are dominant in receptor-anion complexation.
Conclusions:
- Tetraglycine peptides exhibit effective anion recognition capabilities.
- Peptide structure and charge significantly influence anion binding affinity and selectivity.
- Findings guide the design of peptide-based anion receptors for supramolecular applications.
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