Cell-Surface Glyco-Engineering by Exogenous Enzymatic Transfer Using a Bifunctional CMP-Neu5Ac Derivative

Area of Science:

• Biochemistry
• Cell Biology
• Glycobiology

Background:

• Current cell-surface engineering methods often lead to transient molecular presentation or necessitate genetic modification.
• Efficient and stable display of exogenous biomolecules on cell surfaces is crucial for biological studies and therapeutic applications.

Purpose of the Study:

• To develop a robust cell-surface engineering strategy for long-lived, functional display of complex biomolecules.
• To overcome limitations of existing methods requiring genetic manipulation or resulting in short-lived presentations.

Main Methods:

• Utilized a novel CMP-Neu5Ac derivative modified with a synthetic heparan sulfate (HS) oligosaccharide and biotin at the C-5 position.
• Employed recombinant ST6GAL1 enzyme to transfer the modified sialic acid onto N-glycans of living cell glycoproteins.
• Assessed the functional activity of the displayed HS oligosaccharide in restoring protein binding and activating cell signaling.

Main Results:

• Achieved long-lived display of the modified sialic acid and its attached HS oligosaccharide on living cells.
• Demonstrated that the displayed HS oligosaccharide is functionally active, restoring protein binding capabilities.
• Showed activation of cell signaling events in HS-deficient cells upon display of the functional HS oligosaccharide.

Conclusions:

• The developed cell-surface engineering strategy enables stable and functional presentation of complex biomolecules on cell surfaces.
• This method is versatile, adaptable to various cell types, and compatible with a wide range of biomolecules.
• The approach offers a powerful tool for studying cellular processes and developing new biotechnological applications.