Thermodynamic analysis of the binding of galactose and poly-N-acetyllactosamine derivatives to human galectin-3

Sikdera, Kiran Bachhawat and Thomas, Celestine J and Surolia, Avadhesha (2001) Thermodynamic analysis of the binding of galactose and poly-N-acetyllactosamine derivatives to human galectin-3. In: FEBS Letters, 500 (1-2). pp. 75-79.

PDF Thermodynamic_analysis.pdf Restricted to Registered users only Download (226kB) | Request a copy

Abstract

Galectin-3, with a wide tissue distribution and marked developmental regulation, provides significant insights into the progression of various disease and developmental stages. Recognized by its specificity for galactose, a detailed characterization of its sugar binding ability has been investigated by isothermal titration calorimetry. The results presented here complement well with the earlier studies utilizing hapten inhibition assays. Among the various lactose derivatives studied, A-tetrasaccharide emerged with the highest affinity for binding to galectin-3 combining site. This blood group saccharide exhibited a binding affinity 37-fold higher and a 102 kJ/mol more favorable change in enthalpy over lactose at 280 K indicating the existence of additional subsites for both the \alpha 1-3-linked N-acetylgalactosamine at the non-reducing end and the \alpha 1-2-linked L-fucosyl residue. The thermodynamic parameters evaluated for other ligands substantiate further the carbohydrate recognition domain to be part of an extended binding site. Binding thermodynamics of galectin-3 with the galactose derivatives are essentially enthalpically driven and exhibit compensatory changes in $\Delta H^o$ and $T \Delta S$ owing to solvent reorganization.

Item Type:	Journal Article
Publication:	FEBS Letters
Publisher:	Elsevier
Additional Information:	Copyright of this article belongs to Elsevier.
Keywords:	Galectin-3;Isothermal titration calorimetry;Lactose;Blood group saccharide;Enthalpy–entropy compensation
Department/Centre:	Division of Biological Sciences > Molecular Biophysics Unit
Date Deposited:	01 Oct 2007
Last Modified:	19 Sep 2010 04:39
URI:	http://eprints.iisc.ac.in/id/eprint/12016

Actions (login required)

View Item