Related Experiment Video
Updated: Jun 10, 2025

09:07
Concanavalin A-Based Sedimentation Assay to Measure Substrate Binding of Glucan Phosphatases
Published on: December 23, 2022
1.3K
Analysis of Glycan Recognition by Concanavalin A Using Absolute Binding Free Energy Calculations
Sondos Musleh1,2, Irfan Alibay3,4, Philip C Biggin4
1Division of Pharmacy and Optometry, The University of Manchester, Manchester M13 9PT, U.K.
Journal of Chemical Information and Modeling
|October 16, 2024
Summary
Absolute binding free energy calculations accurately predict carbohydrate-protein interactions for concanavalin A, matching experimental data. This method shows promise for designing therapeutics and diagnostics.
Area of Science:
- Biochemistry
- Computational Chemistry
- Structural Biology
Background:
- Carbohydrates mediate crucial biological recognition and signaling.
- Understanding carbohydrate-protein interactions is vital for biological and medical research.
- Concanavalin A is a well-studied lectin, making it an excellent model system.
Purpose of the Study:
- To evaluate the efficacy of absolute binding free energy (ABFE) calculations in predicting carbohydrate ligand affinities for concanavalin A.
- To compare ABFE predictions with experimental microcalorimetry data.
- To assess the ability of ABFE to deconvolute binding contributions of different carbohydrate moieties.
Main Methods:
- Absolute binding free energy (ABFE) calculations were performed.
- Ligand affinities were predicted for five related carbohydrate ligands binding to concanavalin A.
- Results were compared with experimental data from isothermal titration calorimetry (ITC).
Main Results:
- ABFE calculations quantitatively ranked ligand affinities, showing good agreement with microcalorimetry (mean signed error of -0.63 ± 0.04 kcal/mol).
- The method accurately reproduced diminished binding efficiencies for larger carbohydrate ligands, including a pentasaccharide and its components.
- ABFE correctly identified the high affinity of the mannose residue and the low contribution of β-GlcNAc arms in the pentasaccharide.
Conclusions:
- ABFE calculations offer a reliable quantitative tool for predicting carbohydrate-protein binding affinities.
- The method successfully deconvolutes the contributions of individual residues within complex carbohydrate ligands.
- This approach holds significant potential for the rational design of carbohydrate-based therapeutics, vaccines, and diagnostics.
Related Concept Videos
Conserved Binding Sites
4.2K
Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally...
4.2K
The Equilibrium Binding Constant and Binding Strength
12.8K
The equilibrium binding constant (Kb) quantifies the strength of a protein-ligand interaction. Kb can be calculated as follows when the reaction is at equilibrium:
12.8K

