Systematic Structural Characterization of Chitooligosaccharides Enabled by Automated Glycan Assembly

Area of Science:

• Biochemistry
• Polymer Science
• Immunology

Background:

• Chitin and chitosan are abundant biopolymers with significant mechanical and elastic properties.
• Their degradation products, chitooligosaccharides (COS), are known to modulate innate immune responses in both humans and plants.
• The properties and functions of COS are intricately linked to their polymer length, degree of acetylation, and environmental pH.

Purpose of the Study:

• To synthesize well-defined chitooligosaccharides (COS) for systematic structural analysis.
• To investigate the molecular basis of how polymer length and acetylation influence COS properties.
• To elucidate the role of specific molecular interactions in stabilizing COS structures.

Main Methods:

• Automated glycan assembly (AGA) was employed for the rapid synthesis of defined COS.
• Chitin-cellulose hybrid oligomers were prepared as analytical tools.
• Molecular dynamics simulations and Nuclear Magnetic Resonance (NMR) analysis were used to study intramolecular interactions.

Main Results:

• AGA provided efficient access to synthetic, well-defined COS samples.
• Chitin-cellulose hybrid oligomers served as valuable tools for structural investigations.
• Molecular dynamics and NMR analyses identified critical intramolecular interactions, highlighting the stabilizing role of the chitosan amino group.

Conclusions:

• Well-defined COS can be synthesized using AGA, overcoming limitations of previous studies.
• The study provides a molecular understanding of how COS structure dictates function.
• The chitosan amino group plays a key role in stabilizing specific geometries, impacting COS biological activity.