2LI3

Structural and functional analysis of a novel potassium toxin argentinean scorpion Tityus trivittatus reveals a new kappa sub-family

2LI3 の概要

• エントリーDOI: 10.2210/pdb2li3/pdb
• 分子名称: Potassium channel toxin kappa-KTX3.1 (1 entity in total)
• 機能のキーワード: alpha/alpha motif, alpha scorpion toxin, voltage gated potassium channel alpha toxin, toxin
• 由来する生物種: Tityus trivittatus (Argentinean scorpion)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 3334.92

構造登録者

Saucedo-Yanez, A.,Del Rio-Portilla, F.,Hernandez-Lopez, R. (登録日: 2011-08-19, 公開日: 2012-01-11, 最終更新日: 2012-04-25)

主引用文献

Saucedo, A.L.,Flores-Solis, D.,Rodriguez de la Vega, R.C.,Ramirez-Cordero, B.,Hernandez-Lopez, R.,Cano-Sanchez, P.,Navarro, R.N.,Garcia-Valdes, J.,Coronas-Valderrama, F.,de Roodt, A.,Brieba, L.G.,Possani, L.D.,Del Rio-Portilla, F.
New Tricks of an Old Pattern: STRUCTURAL VERSATILITY OF SCORPION TOXINS WITH COMMON CYSTEINE SPACING.
J.Biol.Chem., 287:12321-12330, 2012

PubMed Abstract: Scorpion venoms are a rich source of K(+) channel-blocking peptides. For the most part, they are structurally related small disulfide-rich proteins containing a conserved pattern of six cysteines that is assumed to dictate their common three-dimensional folding. In the conventional pattern, two disulfide bridges connect an α-helical segment to the C-terminal strand of a double- or triple-stranded β-sheet, conforming a cystine-stabilized α/β scaffold (CSα/β). Here we show that two K(+) channel-blocking peptides from Tityus scorpions conserve the cysteine spacing of common scorpion venom peptides but display an unconventional disulfide pattern, accompanied by a complete rearrangement of the secondary structure topology into a CS helix-loop-helix fold. Sequence and structural comparisons of the peptides adopting this novel fold suggest that it would be a new elaboration of the widespread CSα/β scaffold, thus revealing an unexpected structural versatility of these small disulfide-rich proteins. Acknowledgment of such versatility is important to understand how venom structural complexity emerged on a limited number of molecular scaffolds.

PubMed: 22238341
DOI: 10.1074/jbc.M111.329607

実験手法

SOLUTION NMR