Solution Structure of Two New Toxins from the Venom of the Chinese Scorpion Buthus martensi Karsch Blockers of Potassium Channels
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- 作者：Eric Blanc ; Ré ; gine Romi-Lebrun ; Olivier Bornet ; Terumi Nakajima ; and Hervé ; Darbon
- 刊名：Biochemistry
- 出版年：1998
- 出版时间：September 8, 1998
- 年：1998
- 卷：37
- 期：36
- 页码：12412 - 12418
- 全文大小：169K
- 年卷期：v.37,no.36(September 8, 1998)
- ISSN：1520-4995
文摘
The solution structure of BmTX2 purified from the venom of the Chinese Buthid Buthusmartensi has been determined by 2D NMR spectroscopy techniques which led to the description of its3D conformation. The structure consists of a triple-stranded 
-sheet connected to a helical structure.This helix encompasses 10 residues, from 11 to 20, begins with a turn of 310 helix, and ends with an 
helix. The three strands of sheet comprise residues 2-6, with a bulge covering residues 4 and 5,26-29, and 32-35, with a type I' turn centered on residues 30-31. We also characterized the solutionstructure of BmTX1. The two toxins which are potent blockers of both large-conductance calcium-activated potassium channels (BKCa channels) and voltage-gated potassium channels (Kv1.3) are highlysuperimposable and possess the same structural characteristics. Analysis of these structures allows us tohypothesize that, besides the main surface of interaction described by the functional map of charybdotoxin,one can expect that the binding of scorpion toxins on BKCa channels may involve residues on the edgeof this surface.
-sheet connected to a helical structure.This helix encompasses 10 residues, from 11 to 20, begins with a turn of 310 helix, and ends with an helix. The three strands of sheet comprise residues 2-6, with a bulge covering residues 4 and 5,26-29, and 32-35, with a type I' turn centered on residues 30-31. We also characterized the solutionstructure of BmTX1. The two toxins which are potent blockers of both large-conductance calcium-activated potassium channels (BKCa channels) and voltage-gated potassium channels (Kv1.3) are highlysuperimposable and possess the same structural characteristics. Analysis of these structures allows us tohypothesize that, besides the main surface of interaction described by the functional map of charybdotoxin,one can expect that the binding of scorpion toxins on BKCa channels may involve residues on the edgeof this surface.