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Molecular Modeling and Docking Studies of Neu5Ac2en analogues against Cholera toxin

Author Affiliations

  • 1Department of Bioinformatics, Karunya Univesity, Karunya Nagar, Coimabtore-641114, Tamil Nadu, INDIA

Res. J. Recent Sci., Volume 3, Issue (ISC-2013), Pages 408-414, (2014)


Neu5Ac2en (2-deoxy-2, 3-didehydro-N-acetylneuraminic acid) analogues were modified in two different positions C-4 and C-9 were investigated using molecular modeling and molecular docking techniques. Cholera toxin is an protein complex made up of AB5 subunits secreted by the pathogenic organism Vibrio cholerae. In present days these organism shows resistance towards antibiotics. In our present study, Cholera toxin 3D protein structure was optimized and minimized using maestro v9.2. Twelve synthetic Neu5Ac2en analogues were modeled using ACD/ChemSketch and optimized in LigPrep which is a tool in Schrödinger suite. Active site of cholera toxin protein was analyzed using PDBsum database. Molecular docking of Neu5Ac2en analogues into the active site of cholera toxin protein were carried out using Glide v5.7. All the 12 analogues of Neu5Ac2en show good binding affinity towards the cholera toxin with least docking (XPG) energy score and also these analogues have good pharmacological properties. Neu5Ac2en analogues blocks the binding site residues of cholera toxin directly through intermolecular hydrogen bonding.


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