𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Solution structure of potassium channel-inhibiting scorpion toxin Lq2

✍ Scribed by Jean-Guillaume Renisio; Zhe Lu; Eric Blanc; Weili Jin; John H. Lewis; Olivier Bornet; Hervé Darbon

Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
653 KB
Volume
34
Category
Article
ISSN
0887-3585

No coin nor oath required. For personal study only.

✦ Synopsis

Lq2 is a unique scorpion toxin. Acting from the extracellular side, Lq2 blocks the ion conduction pore in not only the voltage-and Ca 2؉ -activated channels, but also the inward-rectifier K ؉ channels. This finding argues that the threedimensional structures of the pores in these K ؉ channels are similar. However, the amino acid sequences that form the external part of the pore are minimally conserved among the various classes of K ؉ channels. Because Lq2 can bind to all the three classes of K ؉ channels, we can use Lq2 as a structural probe to examine how the non-conserved poreforming sequences are arranged in space to form similar pore structures. In the present study, we determined the three-dimensional structure of Lq2 using nuclear magnetic resonance (NMR) techniques. Lq2 consists of an ␣-helix (residues S10 to L20) and a ␤-sheet, connected by an ␣␤3 loop (residues N22 to N24). The ␤-sheet has two well-defined anti-parallel strands (residues G26 to M29 and residues K32 to C35), which are connected by a type I' ␤-turn centered between residues N30 and K31. The N-terminal segment (residues Z1 to T8) appears to form a quasi-third strand of the ␤-sheet.

📜 SIMILAR VOLUMES

Solution structure of P01, a natural sco
Solution structure of P01, a natural scorpion peptide structurally analogous to scorpion toxins specific for apamin-sensitive potassium channel
✍ Blanc, E.; Fremont, V.; Sizun, P.; Meunier, S.; Van Rietschoten, J.; Thevand, A. 📂 Article 📅 1996 🏛 John Wiley and Sons 🌐 English ⚖ 832 KB

The venom of the North African scorpion Androctonus mauretanicus mauretanicus possesses numerous highly active neurotoxins that specifically bind to various ion channels. One of these, P05, has been found to bind specifically to calcium-activated potassium channels and also to compete with apamin, a

Solution structure of maurotoxin, a scor
Solution structure of maurotoxin, a scorpion toxin from Scorpio maurus, with high affinity for voltage-gated potassium channels
✍ E. Blanc; J.M. Sabatier; R. Kharrat; S. Meunier; M. El Ayeb; J. Van Rietschoten; 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 488 KB 👁 2 views

Maurotoxin (MTX), purified from the scorpionid Scorpio maurus is a potent ligand for potassium channels. It shows a broad specificity as being active on Kv1.1 (Kd ‫؍‬ 37 nM), Kv1.2 (Kd ‫؍‬ 0.8 nM), Kv1.3 (Kd ‫؍‬ 150 nM) voltage-gated potassium channels, as well as on small-conductance calcium-activa

Secondary structure of ShK toxin, a pota
Secondary structure of ShK toxin, a potassium-channel-blocking peptide
✍ William R. Kem; Gautam Sanyal; Robert W. Williams; Michael W. Pennington 📂 Article 📅 1996 🏛 Springer Netherlands 🌐 English ⚖ 265 KB

Sea anemones possess small K-channel-blocking peptides about the same size as the scorpion K-channel toxins. We have estimated the secondary structure content (33% helix, 26% ]3-sheet) of one of these toxins, ShK toxin, using CD, Raman, and FTIR spectroscopy. A hypothetical 3D structure of the pepti

Refined solution structure of the anti-m
Refined solution structure of the anti-mammal and anti-insect LqqIII scorpion toxin: Comparison with other scorpion toxins
✍ Céline Landon; Patrick Sodano; Bruno Cornet; Jean-Marc Bonmatin; Charles Kopeyan 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 654 KB

The solution structure of the anti-mammal and anti-insect LqqIII toxin from the scorpion Leiurus quinquestriatus quinquestriatus was refined and compared with other long-chain scorpion toxins. This structure, determined by 1 H-NMR and molecular modeling, involves an a-helix (18-29) linked to a three

Solution structure of BmKTX, a K+ blocke
Solution structure of BmKTX, a K+ blocker toxin from the Chinese scorpion Buthus Martensi
✍ Jean-Guillaume Renisio; Régine Romi-Lebrun; Eric Blanc; Olivier Bornet; Terumi N 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 481 KB

BmKTX is a toxin recently purified from the venom of Buthus Martensi, which belongs to the kaliotoxin family. We have determined its solution structure by use of conventional twodimensional NMR techniques followed by distancegeometry and energy minimization. The calculated structure is composed of a

Solution structure of TsKapa, a charybdo
Solution structure of TsKapa, a charybdotoxin-like scorpion toxin from Tityus serrulatus with high affinity for apamin-sensitive Ca2+-activated K+ channels
✍ E. Blanc; C. Lecomte; J. Van Rietschoten; J.M. Sabatier; H. Darbon 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 802 KB

TsKapa (TsK), purified from the Buthidae Tityus serrulatus is a very high potent ligand for small-conductance apaminsensitive calcium-activated potassium channels (SK). It is able to efficiently compete with apamin for binding on this channel (K 0.5 ‫؍‬ 0.3 nM) [Legros, C. et al., FEBS Lett. 390:81-