1WCT

A NOVEL CONOTOXIN FROM CONUS TEXTILE WITH UNUSUAL POST-TRANSLATIONAL MODIFICATIONS REDUCES PRESYNAPTIC CALCIUM INFLUX, NMR, 1 STRUCTURE, GLYCOSYLATED PROTEIN

1WCT の概要

• エントリーDOI: 10.2210/pdb1wct/pdb
• 分子名称: OMEGAC-TXIX, beta-D-galactopyranose-(1-3)-2-acetamido-2-deoxy-beta-D-galactopyranose (2 entities in total)
• 機能のキーワード: gamma-carboxy glutamic acid, novel omega conotoxin, calcium channel blocker
• 由来する生物種: Conus textile (cloth-of-gold cone)
• 細胞内の位置: Secreted: P81755
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 1953.80

構造登録者

Rigby, A.C.,Hambe, B.,Czerwiec, E.,Baleja, J.D.,Furie, B.C.,Furie, B.,Stenflo, J. (登録日: 1998-12-18, 公開日: 1999-06-08, 最終更新日: 2025-03-26)

主引用文献

Rigby, A.C.,Lucas-Meunier, E.,Kalume, D.E.,Czerwiec, E.,Hambe, B.,Dahlqvist, I.,Fossier, P.,Baux, G.,Roepstorff, P.,Baleja, J.D.,Furie, B.C.,Furie, B.,Stenflo, J.
A conotoxin from Conus textile with unusual posttranslational modifications reduces presynaptic Ca2+ influx.
Proc.Natl.Acad.Sci.USA, 96:5758-5763, 1999

PubMed Abstract: Cone snails are gastropod mollusks of the genus Conus that live in tropical marine habitats. They are predators that paralyze their prey by injection of venom containing a plethora of small, conformationally constrained peptides (conotoxins). We report the identification, characterization, and structure of a gamma-carboxyglutamic acid-containing peptide, conotoxin epsilon-TxIX, isolated from the venom of the molluscivorous cone snail, Conus textile. The disulfide bonding pattern of the four cysteine residues, an unparalleled degree of posttranslational processing including bromination, hydroxylation, and glycosylation define a family of conotoxins that may target presynaptic Ca2+ channels or act on G protein-coupled presynaptic receptors via another mechanism. This conotoxin selectively reduces neurotransmitter release at an Aplysia cholinergic synapse by reducing the presynaptic influx of Ca2+ in a slow and reversible fashion. The three-dimensional structure, determined by two-dimensional 1H NMR spectroscopy, identifies an electronegative patch created by the side chains of two gamma-carboxyglutamic acid residues that extend outward from a cavernous cleft. The glycosylated threonine and hydroxylated proline enclose a localized hydrophobic region centered on the brominated tryptophan residue within the constrained intercysteine region.

PubMed: 10318957
DOI: 10.1073/pnas.96.10.5758

実験手法

SOLUTION NMR