Zaharenko André Junqueira, Ferreira Wilson Alves, de Oliveira Joacir Stolarz, Konno Katsuhiro, Richardson Michael, Schiavon Emanuele, Wanke Enzo, de Freitas José Carlos
Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, n: 321, CEP 05508-900, São Paulo, SP, Brazil.
Toxicon. 2008 Jun 1;51(7):1303-7. doi: 10.1016/j.toxicon.2008.01.011. Epub 2008 Feb 2.
Sodium channel toxins from sea anemones are employed as tools for dissecting the biophysical properties of inactivation in voltage-gated sodium channels. Cangitoxin (CGTX) is a peptide containing 48 amino acid residues and was formerly purified from Bunodosoma cangicum. Nevertheless, previous works reporting the isolation procedures for such peptide from B. cangicum secretions are controversial and may lead to incorrect information. In this paper, we report a simple and rapid procedure, consisting of two chromatographic steps, in order to obtain a CGTX analog directly from sea anemone venom. We also report a substitution of N16D in this peptide sample and the co-elution of an inseparable minor isoform presenting the R14H substitution. Peptides are named as CGTX-II and CGTX-III, and their effects over Nav1.1 channels in patch clamp experiments are demonstrated.
来自海葵的钠通道毒素被用作剖析电压门控钠通道失活生物物理特性的工具。刺尾海葵毒素（CGTX）是一种含有48个氨基酸残基的肽，以前是从刺尾海葵中纯化得到的。然而，先前报道从刺尾海葵分泌物中分离这种肽的程序存在争议，可能会导致错误信息。在本文中，我们报告了一种简单快速的程序，包括两个色谱步骤，以便直接从海葵毒液中获得一种CGTX类似物。我们还报告了该肽样品中N16D的取代以及呈现R14H取代的不可分离的次要异构体的共洗脱。这些肽被命名为CGTX-II和CGTX-III，并在膜片钳实验中证明了它们对Nav1.1通道的作用。
