7RDP

Crystal structure of human galectin-3 CRD in complex with selenodigalactoside

Summary for 7RDP

• Entry DOI: 10.2210/pdb7rdp/pdb
• Descriptor: Galectin-3, beta-D-galactopyranosyl 1-seleno-beta-D-galactopyranoside, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: galectin, carbohydrate-binding protein, sugar binding protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 16198.81

Authors

Kishor, C.,Go, R.M.,Blanchard, H. (deposition date: 2021-07-10, release date: 2022-07-13, Last modification date: 2023-10-18)

Primary citation

Raics, M.,Balogh, A.K.,Kishor, C.,Timari, I.,Medrano, F.J.,Romero, A.,Go, R.M.,Blanchard, H.,Szilagyi, L.,E Kover, K.,Feher, K.
Investigation of the Molecular Details of the Interactions of Selenoglycosides and Human Galectin-3.
Int J Mol Sci, 23:-, 2022

PubMed Abstract: Human galectin-3 (Gal-3) is involved in a variety of biological processes and is implicated in wide range of diseases. As a result, targeting Gal-3 for clinical applications has become an intense area of research. As a step towards the development of novel Gal-3 inhibitors, we describe a study of the binding of two Se-containing Gal-3 inhibitors, specifically that of di(β-D-galactopyranosyl)selenide (SeDG), in which two galactose rings are linked by one Se atom and a di(β-D-galactopyranosyl)diselenide (DSeDG) analogue with a diseleno bond between the two sugar units. The binding affinities of these derivatives to Gal-3 were determined by N-H HSQC NMR spectroscopy and fluorescence anisotropy titrations in solution, indicating a slight decrease in the strength of interaction for SeDG compared to thiodigalactoside (TDG), a well-known inhibitor of Gal-3, while DSeDG displayed a much weaker interaction strength. NMR and FA measurements showed that both seleno derivatives bind to the canonical S face site of Gal-3 and stack against the conserved W181 residue also confirmed by X-ray crystallography, revealing canonical properties of the interaction. The interaction with DSeDG revealed two distinct binding modes in the crystal structure which are in fast exchange on the NMR time scale in solution, explaining a weaker interaction with Gal-3 than SeDG. Using molecular dynamics simulations, we have found that energetic contributions to the binding enthalpies mainly differ in the electrostatic interactions and in polar solvation terms and are responsible for weaker binding of DSeDG compared to SeDG. Selenium-containing carbohydrate inhibitors of Gal-3 showing canonical binding modes offer the potential of becoming novel hydrolytically stable scaffolds for a new class of Gal-3 inhibitors.

PubMed: 35269646
DOI: 10.3390/ijms23052494

Experimental method

X-RAY DIFFRACTION (1.96 Å)