Phosphates as Assisting Groups in Glycan Synthesis.

Area of Science:

• Carbohydrate Chemistry
• Glycobiology
• Biotechnology

Background:

• Biological pathways utilize reversible phosphorylation for regulation.
• Chemical synthesis of complex oligosaccharides faces challenges like aggregation and site-specificity.
• Glycans play crucial roles in various biological processes.

Purpose of the Study:

• To adapt the biological concept of phosphorylation for chemical synthesis of glycans.
• To achieve site-specific enzymatic modification of synthetic glycans.
• To develop a method for solubilizing and isolating aggregating glycans.
• To trigger the self-assembly of glycan nanostructures.

Main Methods:

• Chemical phosphorylation of synthetic glycans at specific sites.
• Enzymatic elongation using sialylation guided by phosphate groups.
• Utilizing phosphates for glycan solubilization and isolation.
• Enzymatic dephosphorylation using alkaline phosphatase.

Main Results:

• Site-specific enzymatic sialylation of glycans was achieved.
• Phosphorylation improved the solubility and isolation of aggregating glycans.
• Traceless removal of phosphates regenerated the native glycan structures.
• The dephosphorylation step triggered the self-assembly of glycan nanostructures.

Conclusions:

• Phosphorylation serves as a versatile tool in synthetic glycobiology.
• This method overcomes limitations in complex glycan synthesis and enables nanostructure formation.
• Enzymatic dephosphorylation is a key step for revealing native structures and initiating assembly.