2DPQ

The crystal structures of the calcium-bound con-G and con-T(K7gamma) dimeric peptides demonstrate a novel metal-dependent helix-forming motif

2DPQ の概要

• エントリーDOI: 10.2210/pdb2dpq/pdb
• 関連するPDBエントリー: 2DPR
• 分子名称: Conantokin-G, CHLORIDE ION, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: conantoxin, con-g, nmdar antagonist, gla-containing, metal binding protein
• 由来する生物種: Conus geographus (Geography cone)
• 細胞内の位置: Secreted: P07231
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 2420.88

構造登録者

Cnudde, S.E.,Prorok, M.,Dai, Q.,Castellino, F.J.,Geiger, J.H. (登録日: 2006-05-13, 公開日: 2007-04-24, 最終更新日: 2024-04-03)

主引用文献

Cnudde, S.E.,Prorok, M.,Dai, Q.,Castellino, F.J.,Geiger, J.H.
The crystal structures of the calcium-bound con-G and con-T[K7gamma] dimeric peptides demonstrate a metal-dependent helix-forming motif
J.Am.Chem.Soc., 129:1586-1593, 2007

PubMed Abstract: Short peptides that have the ability to form stable alpha-helices in solution are rare, and a number of strategies have been used to produce them, including the use of metal chelation to stabilize folding of the backbone. However, no example exists of a structurally well-defined helix stabilized exclusively through metal ion chelation. Conantokins (con)-G and -T are short peptides that are potent antagonists of N-methyl-D-aspartate receptor channels. While con-G exhibits no helicity alone, it undergoes a structural transition to a helical conformation in the presence of a variety of multivalent cations, especially Mg2+ and Ca2+. This complexation also results in antiparallel dimerization of two peptide helices in the presence of Ca2+, but not Mg2+. A con-T variant, con-T[K7gamma], displays very similar behavior. We have solved the crystal structures of both Ca2+/con-G and Ca2+/con-T [K7gamma] at atomic resolution. These structures clearly show the nature of the metal-dependent dimerization and helix formation and surprisingly also show that the con-G dimer interface is completely different from the con-T[K7gamma] interface, even though the metal chelation is similar in the two peptides. This represents a new paradigm in helix stabilization completely independent of the hydrophobic effect, which we define as the "metallo-zipper."

PubMed: 17243678
DOI: 10.1021/ja065722q

実験手法

X-RAY DIFFRACTION (1.25 Å)