Related Experiment Video
Updated: May 20, 2025
05:28
Demonstration of Heterologous Complexes formed by Golgi-Resident Type III Membrane Proteins using Split Luciferase Complementation Assay
Published on: September 10, 2020
2.3K
Structure-Based Mechanism and Specificity of Human Galactosyltransferase β3GalT5
Jennifer M Lo1,2,3, Chih-Chuan Kung1, Ting-Jen Rachel Cheng1
1Genomics Research Center, Academia Sinica, Taipei 115, Taiwan.
Journal of the American Chemical Society
|March 25, 2025
Summary
Human β1,3-galactosyltransferase 5 (β3GalT5) is crucial for cancer progression. This study reveals its structure and catalytic mechanism, offering insights for developing new anticancer drugs targeting glycan synthesis.
Area of Science:
- Biochemistry
- Structural Biology
- Glycobiology
Background:
- Human β1,3-galactosyltransferase 5 (β3GalT5) is vital in synthesizing glycans implicated in cancer.
- β3GalT5 is a promising target for novel anticancer therapies.
Purpose of the Study:
- To elucidate the X-ray structures of β3GalT5 in complex with substrates and analogues.
- To determine the catalytic mechanism and substrate specificity of β3GalT5.
Main Methods:
- X-ray crystallography of β3GalT5 with UDP-galactose and UDP-2-fluorogalactose.
- Analysis of enzyme complexes with various glycan acceptors at different reaction stages.
Main Results:
- Determined structures of β3GalT5 complexes, revealing galactose transfer via an SN2-like mechanism.
- Observed alternative UDP-galactose hydrolysis products (galactose, oxocarbenium-like) via SN2 and SN1-like pathways in the absence of acceptors.
Conclusions:
- The study advances understanding of enzymatic glycosylation by β3GalT5.
- Structural and mechanistic insights provide a basis for drug design targeting β3GalT5 in cancer.
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