Abstract: BmK CT,one of the key toxin from Buthus matensii Karsch,has been shown to bind specifically to glioma cell surface as a specific chloride channel blocker.In this study,three dimensional structure of BmK CT was modeled and the crystallization condition of BmK CT was filtrated.Prediction of three dimensional structure of BmK CT was performed by SWISS-MODEL workspace and the quality of generated mode was further examined by energy minimization and molecular dynamics (MD)simulation using Insight II 2000 software package.Crystallization of BmK CT was performed using the hanging-drop method.51 conditions (Crystal Screening Kit,Hampton Research)were used to get good quality and well repeating crystals.The structure of BmK CT and Cltx consisted of a small three-stranded antiparallel β-sheet packed against an α-helix.But BmK CT belonged to βαβ type and Cltx αββ type.The calculated electrostatic potential surface around the BmK CT and Cltx molecule were found to be mainly positive,which suggested that this clustering of positively charged residues and the strong positive field they produce might well have important implications on the interaction with the receptors.The results showed that hexagonal column crystal could be obtained from a condition containing 1.4 mol/L sodium acetate,0.1 mol/L Na cacodylate,pH 6.51,at 4℃ and the protein was dissolved in ddH₂O.

Key words: BmK CT, Prediction of three dimensional structures, Electrostatic potential surface, Crystallization

CLC Number: 

• Q78