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Comparative Modeling, Toxin-Ion Channel Interactions, Quantum Based Molecular Dynamics and Simulation Studies on Potassium Channel Toxin Alpha-KTx 1.11 Blockers, Slotoxin from Centruroides Noxius

R. Barani Kumar, M. Xavier Suresh


A serious of biological studies proves the functions of ion channel proteins and its function. Toxin is one of the best tool reveals the information about ion channels. Slotoxin, fromCentruroides noxius plays an important role on blocking of calcium activated potassium channels. In this study we predicted 3D structure slotoxin using comparative modeling method. The predicted model shows 100% residues in allowed conformation. Then protein-protein interaction studies were performed with ion channel protein using ZDOCK and refined with RDOCK and obtained best RDock score of 96.331. Molecular dynamics (MD) simulation studies carried out to know the binding potency and intermolecular interactions. From the overall study we identified the key residues responsible for inhibitions are Thr1, Cys7, Thr8, Lys11, Cys28, Lys31 and Tyr36. The total energy of the protein-protein complex were -7830.152 kcal/mol. The result of these studies will used for identifying a better inhibitor to neutralize the effect of toxin in future.


Slotoxin, Comparative Modeling, ZDock, RDock, Molecular Dynamics, Ion Channel, Simulation

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