1WT8

Solution Structure of BmP08 from the Venom of Scorpion Buthus martensii Karsch, 20 structures

Summary for 1WT8

• Entry DOI: 10.2210/pdb1wt8/pdb
• Related: 1ACW 1DU9 1PNH 1SCY
• NMR Information: BMRB: 6037
• Descriptor: Neurotoxin BmK X (1 entity in total)
• Functional Keywords: alpha/beta scaffold, toxin
• Biological source: Mesobuthus martensii (Chinese scorpion)
• Cellular location: Secreted: Q7Z0H4
• Total number of polymer chains: 1
• Total formula weight: 3333.88

Authors

Wu, H.,Chen, X.,Tong, X.,Li, Y.,Zhang, N.,Wu, G. (deposition date: 2004-11-17, release date: 2005-04-19, Last modification date: 2024-10-23)

Primary citation

Chen, X.,Li, Y.,Tong, X.,Zhang, N.,Wu, G.,Zhang, Q.,Wu, H.
Solution structure of BmP08, a novel short-chain scorpion toxin from Buthus martensi Karsch.
Biochem.Biophys.Res.Commun., 330:1116-1126, 2005

PubMed Abstract: A novel short-chain scorpion toxin BmP08 was purified from the venom of the Chinese scorpion Buthus martensi Karsch by a combination of gel-filtration, ion exchange, and reversed-phase chromatography. The primary sequence of BmP08 was determined using the tandem MS/MS technique and Edman degradation, as well as results of NMR sequential assignments. It is composed of 31 amino acid residues including six cysteine residues and shares less than 25% sequence identity with the known alpha-KTx toxins. BmP08 shows no inhibitory activity on all tested voltage-dependent and Ca(2+)-activated potassium channels. The 3D-structure of BmP08 has been determined by 2D-NMR spectroscopy and molecular modeling techniques. This toxin adopts a common alpha/beta-motif, but shows a distinctive local conformation and features a 3(10)-helix and a shorter beta-sheet. The unique structure is closely related to the distinct primary sequence of the toxin, especially to the novel arrangement of S-S linkages in the molecule, in which two disulfide bridges (C(i)-C(j) and C(i+3)-C(j+3)) link covalently the 3(10)-helix with one strand of the beta-sheet structure. The electrostatic potential surface analysis of the toxin reveals salt bridges and hydrogen bonds between the basic residues and negatively charged residues nearby in BmP08, which may be unfavorable for its binding with the known voltage-dependent and Ca(2+)-activated potassium channels. Thus, finding the target for this toxin should be an interesting task in the future.

PubMed: 15823559
DOI: 10.1016/j.bbrc.2005.03.084

Experimental method

SOLUTION NMR