1EMX
SOLUTION STRUCTURE OF HPTX2, A TOXIN FROM HETEROPODA VENATORIA SPIDER VENOM THAT BLOCKS KV4.2 POTASSIUM CHANNEL
Summary for 1EMX
| Entry DOI | 10.2210/pdb1emx/pdb |
| Descriptor | HETEROPODATOXIN 2 (1 entity in total) |
| Functional Keywords | toxin |
| Biological source | Heteropoda venatoria (giant crab spider) |
| Total number of polymer chains | 1 |
| Total formula weight | 3422.87 |
| Authors | Bernard, C.,Legros, C.,Ferrat, G.,Bishoff, U.,Marquardt, A.,Pongs, O.,Darbon, H. (deposition date: 2000-03-20, release date: 2001-01-24, Last modification date: 2024-10-30) |
| Primary citation | Bernard, C.,Legros, C.,Ferrat, G.,Bischoff, U.,Marquardt, A.,Pongs, O.,Darbon, H. Solution structure of hpTX2, a toxin from Heteropoda venatoria spider that blocks Kv4.2 potassium channel. Protein Sci., 9:2059-2067, 2000 Cited by PubMed Abstract: HpTX2 is a toxin from the venom of Heteropoda venatoria spider that has been demonstrated to bind on Kv4.2 potassium channel. We have determined the solution structure of recombinant HpTX2 by use of conventional two-dimensional NMR techniques followed by distance-geometry and molecular dynamics. The calculated structure belongs to the Inhibitory Cystin Knot structural family that consists in a compact disulfide-bonded core, from which four loops emerge. A poorly defined two-stranded antiparallel beta-sheet (residues 20-23 and 25-28) is detected. Analysis of the electrostatic charge anisotropy allows us to propose a functional map of HpTX2 different from the one described for kappa-conotoxin PVIIA, but strongly related to the one of charybdotoxin. The orientation of the dipole moment of HpTX2 emerges through K27 which could therefore be the critical lysine residue. Close to this lysine are a second basic residue, R23, an aromatic cluster (F7, W25, W30) and an hydrophobic side chain (L24). The high density in aromatic side chains of the putative functional surface as well as the lack of an asparagine is proposed to be the structural basis of the specificity of HpTX2 toward Kv4.2 channel. PubMed: 11152117PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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