Related Experiment Video
Updated: Sep 20, 2025
12:06
Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
Published on: November 25, 2017
12.9K
N-Acetyl Side-Chain Conformation in Saccharides: Solution Models Obtained from MA'AT Analysis
Reagan J Meredith1, Timothy Tetrault1, Mi-Kyung Yoon1
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670 United States.
The Journal of Organic Chemistry
|June 10, 2022
Summary
MA
Area of Science:
- Carbohydrate Chemistry
- Computational Chemistry
- Structural Biology
Background:
- N-acetyl side-chains in GlcNAc and ManNAc are crucial for biological functions.
- Understanding the conformational properties of these monosaccharides is essential for elucidating their roles.
Purpose of the Study:
- To model the conformational properties of N-acetyl side-chains in GlcNAc and ManNAc using MA'AT analysis.
- To determine the C1-C2-N2-C1' torsion angle (θ1) in solution and compare with molecular dynamics simulations.
Main Methods:
- MA'AT analysis combined with Density Functional Theory (DFT) calculations.
- Experimental measurement of spin-coupling constants (J-couplings) in selectively 13C-labeled compounds using NMR spectroscopy.
- Comparison of MA'AT models with experimental data and molecular dynamics (MD) simulations.
Main Results:
- MA'AT analysis accurately modeled the θ1 torsion angle for αGlcNAc, βGlcNAc, and αManNAc residues in solution.
- MA'AT models showed better agreement with experimental J-couplings than MD models.
- N-acetylation was found to conformationally constrain side-chain bonds, similar to O-acetylation.
Conclusions:
- MA'AT analysis is a valuable experimental tool for studying molecular torsion angles in solution.
- The method complements molecular dynamics simulations for conformational analysis.
- MA'AT analysis can detect subtle conformational changes induced by modifications like N-acetylation.
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