1M2S
Solution Structure of A New Potassium Channels Blocker from the Venom of Chinese Scorpion Buthus martensi Karsch
Summary for 1M2S
| Entry DOI | 10.2210/pdb1m2s/pdb |
| Related | 1BIG 1LIR 2BMT 2CRD |
| Descriptor | Toxin BmTX3 (1 entity in total) |
| Functional Keywords | alpha/beta scaffold, toxin |
| Biological source | Mesobuthus martensii (Chinese scorpion) |
| Cellular location | Secreted: Q9NBG9 |
| Total number of polymer chains | 1 |
| Total formula weight | 4069.69 |
| Authors | |
| Primary citation | Wang, Y.,Chen, X.,Zhang, N.,Wu, G.,Wu, H. The solution structure of BmTx3B, a member of the scorpion toxin subfamily alpha-KTx 16 Proteins, 58:489-497, 2005 Cited by PubMed Abstract: This article reports the solution structure of BmTx3B (alpha-KTx16.2), a potassium channel blocker belonging to the subfamily alpha-KTx16, purified from the venom of the Chinese scorpion Buthus martensi Karsch. In solution, BmTx3B assumes a typical CSalphabeta motif, with an alpha-helix connected to a triple-stranded beta-sheet by 3 disulfide bridges, which belongs to the first structural group of short-chain scorpion toxins. On the other hand, BmTx3B is quite different from other toxins (such as ChTx and AgTx2) of this group in terms of the electrostatic and hydrophobic surface distribution. The functional surface (beta-face) of the molecule is characterized by less basic residues (only 2: Lys28 and Arg35) and extra aromatic residues (Phe1, Phe9, Trp15, and Tyr37). The peptide shows a great preference for the Kca1.1 channel over the Kv channel (about a 10(3)-fold difference). The model of BmTx3B/Kca1.1 channel complex generated by docking and dynamic simulation reveals that the stable binding between the BmTx3B and Kca1.1 channel is favored by a number of aromatic pi-pi stacking interactions. The influences of these structural features on the kinetic behavior of the toxin binding to Kca1.1 channel are also discussed. PubMed: 15558557DOI: 10.1002/prot.20322 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
Download full validation report
