AI Article Synopsis
- Computational models provide valuable insights into the molecular conformations and interactions of long polysaccharides in aqueous solutions, which are difficult to obtain through other methods.
- An efficient coarse-grained model for polysaccharides is developed based on detailed all-atom simulations and validated against experimental data for Chitosan, showing strong agreement with real-world results.
- The study reveals that variations in the free energy of glycosidic linkages, influenced by factors like polymer length and deacetylation, significantly impact the properties of the polymers in different pH and ionic strength conditions.
Article Abstract
Computational models can provide detailed information about molecular conformations and interactions in solution, which is currently inaccessible by other means in many cases. Here we describe an efficient and precise coarse-grained model for long polysaccharides in aqueous solution at different physico-chemical conditions such as pH and ionic strength. The Model is carefully constructed based on all-atom simulations of small saccharides and metadynamics sampling of the dihedral angles in the glycosidic links, which represent the most flexible degrees of freedom of the polysaccharides. The model is validated against experimental data for Chitosan molecules in solution with various degree of deacetylation, and is shown to closely reproduce the available experimental data. For long polymers, subtle differences of the free energy maps of the glycosidic links are found to significantly affect the measurable polymer properties. Therefore, for titratable monomers the free energy maps of the corresponding links are updated according to the current charge of the monomers. We then characterize the microscopic and mesoscopic structural properties of large chitosan polysaccharides in solution for a wide range of solvent pH and ionic strength, and investigate the effect of polymer length and degree and pattern of deacetylation on the polymer properties.
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|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5521771 | PMC |
| http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0180938 | PLOS |
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