...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of biochemical and molecular toxicology >Molecular cloning, genomic organization and functional characterization of a new short-chain potassium channel toxin-like peptide BmTxKS4 from Buthus martensii Karsch(BmK).
【24h】

Molecular cloning, genomic organization and functional characterization of a new short-chain potassium channel toxin-like peptide BmTxKS4 from Buthus martensii Karsch(BmK).

机译：来自马氏芽孢杆菌的新型短链钾通道毒素样肽BmTxKS4的分子克隆，基因组组织和功能表征。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Scorpion venom contains many small polypeptide toxins, which can modulate Na(+), K(+), Cl(-), and Ca(2+) ion-channel conductance in the cell membrane. A full-length cDNA sequence encoding a novel type of K(+)-channel toxin (named BmTxKS4) was first isolated and identified from a venom gland cDNA library of Buthus martensii Karsch (BmK). The encoded precursor contains 78 amino acid residues including a putative signal peptide of 21 residues, propeptide of 11 residues, and a mature peptide of 43 residues with three disulfide bridges. BmTxKS4 shares the identical organization of disulfide bridges with all the other short-chain K(+)-channel scorpion toxins. By PCR amplification of the genomic region encoding BmTxKS4, it was shown that BmTxKS4 composed of two exons is disrupted by an intron of 87 bp inserted between the first and the second codes of Phe (F) in the encoding signal peptide region, which is completely identical with that of the characterized scorpion K(+)-channel ligands in the size, position,consensus junctions, putative branch point, and A+T content. The GST-BmTxKS4 fusion protein was successfully expressed in BL21 (DE3) and purified with affinity chromatography. About 2.5 mg purified recombinant BmTxKS4 (rBmTxKS4) protein was obtained by treating GST-BmTxKS4 with enterokinase and sephadex chromatography from 1 L bacterial culture. The electrophysiological activity of 1.0渭M rBmTxKS4 was measured and compared by whole cell patch-clamp technique. The results indicated that rBmTxKS4 reversibly inhibited the transient outward K(+) current (I(to)), delayed inward rectifier K(+) current (I(k1)), and prolonged the action potential duration of ventricular myocyte, but it has no effect on the action potential amplitude. Taken together, BmTxKS4 is a novel subfamily member of short-strain K(+)-channel scorpion toxin. (c) 2004 Wiley Periodicals, Inc. J Biochem Mol Toxicol 18:187-195, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20026.
机译：蝎毒含有许多小的多肽毒素，可调节细胞膜中的Na（+），K（+），Cl（-）和Ca（2+）离子通道电导。首先从Buthus martensii Karsch（BmK）的毒腺cDNA文库中分离并鉴定了编码新型K（+）通道毒素（称为BmTxKS4）的全长cDNA序列。编码的前体包含78个氨基酸残基，包括21个残基的假定信号肽，11个残基的前肽和具有三个二硫键的43个残基的成熟肽。 BmTxKS4与所有其他短链K（+）通道蝎子毒素共享相同的二硫键结构。通过PCR扩增编码BmTxKS4的基因组区域，显示由两个外显子组成的BmTxKS4被87 bp内含子破坏，该内含子插入在编码信号肽区域的Phe（F）第一和第二个密码之间，在大小，位置，共识连接，推定分支点和A + T含量方面与特征化的蝎子K（+）-通道配体完全相同。 GST-BmTxKS4融合蛋白在BL21（DE3）中成功表达，并用亲和层析纯化。通过用肠激酶和Sephadex色谱法处理GST-BmTxKS4，从1 L细菌培养物中获得约2.5 mg纯化的重组BmTxKS4（rBmTxKS4）蛋白。通过全细胞膜片钳技术测量并比较了1.0μMrBmTxKS4的电生理活性。结果表明，rBmTxKS4可逆性抑制瞬时向外K（+）电流（I（to）），延迟向内整流K（+）电流（I（k1）），并延长了心室肌细胞的动作电位持续时间，但它具有对动作电位振幅没有影响。两者合计，BmTxKS4是短株K（+）通道蝎毒的一个新的亚科成员。 （c）2004 Wiley Periodicals，Inc. J Biochem Mol Toxicol 18：187-195，2004;在线发布于Wiley InterScience（www.interscience.wiley.com）。 DOI 10.1002 / jbt.20026。

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号