1B3C
SOLUTION STRUCTURE OF A BETA-NEUROTOXIN FROM THE NEW WORLD SCORPION CENTRUROIDES SCULPTURATUS EWING
Summary for 1B3C
| Entry DOI | 10.2210/pdb1b3c/pdb |
| Descriptor | PROTEIN (NEUROTOXIN CSE-I) (1 entity in total) |
| Functional Keywords | scorpion neurotoxin, new world toxin, toxin |
| Biological source | Centruroides sculpturatus (bark scorpion) |
| Total number of polymer chains | 1 |
| Total formula weight | 7299.31 |
| Authors | Jablonsky, M.J.,Jackson, P.L.,Trent, J.O.,Watt, D.D.,Krishna, N.R. (deposition date: 1998-12-08, release date: 1998-12-16, Last modification date: 2024-10-30) |
| Primary citation | Jablonsky, M.J.,Jackson, P.L.,Trent, J.O.,Watt, D.D.,Krishna, N.R. Solution structure of a beta-neurotoxin from the New World scorpion Centruroides sculpturatus Ewing. Biochem.Biophys.Res.Commun., 254:406-412, 1999 Cited by PubMed Abstract: We report the detailed solution structure of the 7.2 kDa protein CsE-I, a beta-neurotoxin from the New World scorpion Centruroides sculpturatus Ewing. This toxin binds to sodium channels, but unlike the alpha-neurotoxins, shifts the voltage of activation toward more negative potentials causing the membrane to fire spontaneously. Sequence-specific proton NMR assignments were made using 600 MHz 2D-NMR data. Distance geometry and dynamical simulated annealing refinements were performed using experimental distance and torsion angle constraints from NOESY and pH-COSY data. A family of 40 structures without constraint violations was generated, and an energy-minimized average structure was computed. The backbone conformation of the CsE-I toxin shows similar secondary structural features as the prototypical alpha-neurotoxin, CsE-v3, and is characterized by a short 2(1/2)-turn alpha-helix and a 3-strand antiparallel beta-sheet, both held together by disulfide bridges. The RMSD for the backbone atoms between CsE-I and CsE-v3 is 1.48 A. Despite this similarity in the overall backbone folding, the these two proteins show some important differences in the primary structure (sequence) and electrostatic potential surfaces. Our studies provide a basis for unravelling the role of these differences in relation to the known differences in the receptor sites on the voltage sensitive sodium channel for the alpha- and beta-neurotoxins. PubMed: 9918851DOI: 10.1006/bbrc.1998.9904 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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