Solution Structure of BmBKTx1, a New BKCa1 Channel Blocker from the Chinese Scorpion Buthus martensi Karsch
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- 作者：Zheng Cai ; Chenqi Xu ; Yingqi Xu ; Wuyuan Lu ; Cheng-wu Chi ; Yunyu Shi ; and ; and Jihui Wu
- 刊名：Biochemistry
- 出版年：2004
- 出版时间：April 6, 2004
- 年：2004
- 卷：43
- 期：13
- 页码：3764 - 3771
- 全文大小：385K
- 年卷期：v.43,no.13(April 6, 2004)
- ISSN：1520-4995
文摘
BmBKTx1 is a 31-amino acid peptide identified from the venom of the Chinese scorpionButhus martensi Karsch, blocking high-conductance calcium-activated potassium channels. Sequencehomology analysis indicates that BmBKTx1 is a new subfamily of short-chain 
-KTx toxins of thepotassium channel, which we term -KTx19. Synthetic BmBKTx1 was prepared by using solid-phasepeptide synthesis. Two-dimensional NMR spectroscopy techniques were used to determine the solutionstructure of BmBKTx1. The results show that the BmBKTx1 forms a typical cysteine-stabilized /
scaffoldadopted by most short-chain scorpion toxins. The structure of BmBKTx1 consists of a two-strandedantiparallel -sheet (residues 20-29) and an -helix (residues 5-15). The three-dimensional structure ofBmBKTx1 was also compared with those of two function-related scorpion toxins, charybdotoxin (ChTx)and BmTx1, and their structural and functional implications are discussed.
-KTx toxins of thepotassium channel, which we term -KTx19. Synthetic BmBKTx1 was prepared by using solid-phasepeptide synthesis. Two-dimensional NMR spectroscopy techniques were used to determine the solutionstructure of BmBKTx1. The results show that the BmBKTx1 forms a typical cysteine-stabilized / scaffoldadopted by most short-chain scorpion toxins. The structure of BmBKTx1 consists of a two-strandedantiparallel -sheet (residues 20-29) and an -helix (residues 5-15). The three-dimensional structure ofBmBKTx1 was also compared with those of two function-related scorpion toxins, charybdotoxin (ChTx)and BmTx1, and their structural and functional implications are discussed.