title: Solution structure of CnErg1 (Ergtoxin), a HERG specific scorpion toxin.
abstract: The three-dimensional structure of chemically synthesized CnErg1 (Ergtoxin), which specifically blocks HERG (human ether-a-go-go-related gene) K+ channels, was determined by nuclear magnetic resonance spectroscopy. CnErg1 consists of a triple-stranded beta-sheet and an alpha-helix, as is typical of K+ channel scorpion toxins. The peptide structure differs from the canonical structures in that the first beta-strand is shorter and is nearer to the second beta-strand rather than to the third beta-strand on the C-terminus. There is also a large hydrophobic patch on the surface of the toxin, surrounding a central lysine residue, Lys13. We postulate that this hydrophobic patch is likely to form part of the binding surface of the toxin.
authors.affiliation: School of Molecular and Microbial Biosciences, University of Sydney, NSW 2006, Australia. a.torres@mmb.usyd.edu.au
authors.forename: Allan M
authors.initials: AM
authors.lastname: Torres
authors.forename: Paramjit
authors.initials: P
authors.lastname: Bansal
authors.forename: Paul F
authors.initials: PF
authors.lastname: Alewood
authors.forename: Jane A
authors.initials: JA
authors.lastname: Bursill
authors.forename: Philip W
authors.initials: PW
authors.lastname: Kuchel
authors.forename: Jamie I
authors.initials: JI
authors.lastname: Vandenberg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D027682:Cation Transport Proteins; D051638:Ether-A-Go-Go Potassium Channels; D008958:Models, Molecular; D008969:Molecular Sequence Data; D015221:Potassium Channels / Q000187:drug effects*; D024642:Potassium Channels, Voltage-Gated; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012604:Scorpion Venoms / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D012605:Scorpions
chemical_list: D027682:Cation Transport Proteins; D051638:Ether-A-Go-Go Potassium Channels; C092509:KCNH6 protein, human; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D012604:Scorpion Venoms; C118951:ergotoxin, Centruroides noxius