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Updated: May 12, 2026
09:54
Identification and Characterization of Protein Glycosylation using Specific Endo- and Exoglycosidases
Published on: December 26, 2011
A Photoactivatable Glycoenzyme Platform for Spatiotemporally Controlled, Protein-Selective, and In Vivo Glycan
Xiaocui Zheng1, Wanqing Wei1,2,3, Changjiang Wang1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Journal of the American Chemical Society
|March 2, 2026
Summary
Researchers developed GLOBE, a platform for optical control of cell-surface sugar modifications. This method uses light to precisely regulate glycoenzyme activity, enabling targeted glycan oxidation and editing in cells and tissues.
Area of Science:
- Biochemistry
- Chemical Biology
- Glycoscience
Background:
- Cell-surface glycosylation is complex and difficult to control precisely.
- Dynamic and spatially intricate nature of glycans presents challenges for targeted manipulation.
Purpose of the Study:
- To present GLOBE, a novel platform for optical regulation of glycoenzyme activity.
- To enable precise, spatiotemporal control over cell-surface glycosylation.
- To demonstrate applications in glycan oxidation, selective targeting, and in vivo editing.
Main Methods:
- Site-specific incorporation of photocaged unnatural amino acids (ONBY) into glycoenzymes (e.g., galactose oxidase).
- Optical activation using light to control enzyme activity.
- Integration with targeting aptamers for protein selectivity.
- Development of photoresponsive cascades for sequential glycan modification.
- Utilizing upconversion nanoparticles for in vivo photoactivation.
Main Results:
- Achieved micrometer-scale spatial and temporal resolution of cell-surface glycan oxidation.
- Demonstrated binding-gated and protein-selective glycan oxidation using MUC1-targeting aptamers.
- Successfully implemented orthogonal photoresponsive cascades for enhanced labeling.
- Enabled in vivo glycan editing in a murine tumor model via nanoparticle-assisted photoactivation.
Conclusions:
- GLOBE offers a modular and programmable framework for probing and manipulating glycosylation.
- Provides precise spatiotemporal control at single-cell and tissue levels.
- Represents a versatile strategy for investigating and engineering the biological sugar code.
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