Structural study of biologically significant ligands with major birch pollen allergen Betv1 by docking and molecular dynamics simulation.

The major birch pollen allergen, Betv1 of Betula verrucosa is the main causative agent of birch pollen allergy in humans. Betv1 is capable of binding several physiological ligands including fatty acids, flavones, cytokinins and sterols. Until now, no structural information from crystallography or NMR is available regarding binding mode of any of these ligands into the binding pocket of Betv1. In the present study thirteen ligands have been successfully docked into the hydrophobic cavity of Betv1 and binding free energies of the complexes have been calculated using AutoDock 3.0.5. A linear relationship with correlation coefficient (R²) of 0.6 is obtained between ΔG(b)s values plotted against their corresponding IC50 values. The complex formed between Betv1 and the best docking pose for each ligand has been optimized by molecular dynamics simulation. Here, we describe the ligand binding of Betv1, which provides insight into the biological function of this protein. This knowledge is required for structural alteration or inhibition of some of these ligands in order to modify the allergenic properties of this protein.