v5.1.0.3
Cicer data from the Legume Information System
Type | Family |
Description | The Ergtoxin (ErgTx) family is a class of peptides from scorpion venom that specifically block ERG (ether-a-go-go-related gene) K+ channels of the nerve, heart and endocrine cells [ , , ]. Peptides of the ErgTx family have from 42 to 47 amino acid residues cross-linked by four disulphide bridges. The four disulphide bridges have been assigned as C1-C4, C2-C6, C3-C7 and C5-C8 (see the schematic representation below) [ ]. ErgTxs consist of a triple-stranded β-sheet and an α-helix, as is typical of K+ channel scorpion toxins. There is a large hydrophobic patch on the surface of the toxin, surrounding a central lysine residue located near the β-hairpin loop between the second and third strands of the β-sheet. It has been postulated that this hydrophobic patch is likely to form part of the binding surface of the toxin []. Peptides of the ErgTx family possess a Knottin scaffold (see https://www.dsimb.inserm.fr/KNOTTIN/). Some proteins known to belong to the ErgTx family are listed below: ErgTx1, ErgTx2 and ErgTx3 from Centruroides elegans (Bark scorpion). ErgTx1, ErgTx2, ErgTx3 and ErgTx4 from Centruroides exilicauda (Bark scorpion). ErgTx1, ErgTx2 and ErgTx3 from Centruroides gracilis (Slenderbrown scorpion) (Florida bark scorpion). ErgTx1, ErgTx2, ErgTx3 and ErgTx4 from Centruroides limpidus limpidus (Mexican scorpion). ErgTx1, ErgTx2, ErgTx3, ErgTx4, ErgTx5 and gamma-KTx 4.12 from Centruroides sculpturatus (Bark scorpion). ErgTx, ErgTx2, ErgTx3, ErgTx4 and ErgTx5 from Centruroides noxius (Mexican scorpion). |
Short Name | Ergtoxin |