Novel Reversible Fluorescent Glycan Linker for Functional Glycomics

Area of Science:

• Carbohydrate Chemistry
• Glycobiology
• Bioconjugation Chemistry

Background:

• Generating complex glycan libraries is crucial for functional glycomics.
• Existing methods for glycan derivatization lack efficiency and reliability.
• Need for methods that preserve glycan structural integrity.

Purpose of the Study:

• To develop a novel, efficient, and reversible method for glycan derivatization.
• To create a fluorescent linker for generating diverse natural glycan libraries.
• To enable structural analysis and functional studies of glycans.

Main Methods:

• Development of a reversible, cleavable bifunctional linker: 3-(methoxyamino)propylamine (MAPA).
• Synthesis of the fluorescent Fmoc-protected version (F-MAPA).
• Derivatization of free reducing glycans to form closed-ring structures.
• Creation of covalent glycan microarrays using N-hydroxysuccinimide chemistry.
• Large-scale glycan derivatization and linker recycling.
• Generation of neoglycoproteins.
• Reversible cleavage of the MAPA linker for glycan regeneration.

Main Results:

• F-MAPA efficiently derivatizes glycans, forming stable closed-ring structures.
• Glycan microarrays generated using F-MAPA were successfully probed by lectins and antibodies.
• The derivatization process is scalable and the F-MAPA reaction system is recyclable up to five times.
• MAPA-glycans can be readily conjugated to proteins to form neoglycoproteins.
• The MAPA linker allows for efficient 'catch-and-release' of glycans for structural analysis.

Conclusions:

• The F-MAPA linker provides a versatile and efficient tool for generating complex glycan libraries.
• This method preserves glycan integrity and facilitates functional glycomics studies.
• The reversible cleavage feature is critical for detailed structural characterization of natural glycans.