|PROSITE documentation PDOC51862|
Scorpion venoms are complex mixture of peptides with a variety of pharmacological functions. These toxin peptides include ion channel modulators, antibacterial peptides, and protease inhibitors. Scorpion toxins targeting various ion channels share a cysteine-stabilized α/β (CS-α/β) structure, which can be divided into two types: short-chain toxins of 23–42 amino acid residues with 3 or 4 disulfide bridges, which are commonly potassium channel blockers, and long-chain toxins of 53–78 amino acids, which are mostly modulators of sodium channels.
In addition to the classic short-chain toxins such as α-KTxs, which are specific for potassium channels, long-chain toxins with unique structure and function, which were named β-KTxs and scorpine-like peptides, were identified from the scorpion families Buthidae, Scorpionidae and Caraboctonidae. Peptides of the βSPN (β-KTxs and scorpines) family, which are 59–75 amino acid residues in length, display various antimicrobial, cytolytic, and potassium channel-blocking activities. βSPN family full-length mature peptides contain two structural domains that confer them bi-functionality: the amphipathic α-helical N-terminal domain has cytolytic or antimicrobial activity, while the three-disulfid bridged C-terminal domain with the consensus CS-α/β motif has K(+) channel blocking activity. Sequence analysis revealed that the βSPN family can be divided into three distinct groups: (1) β-KTx-like peptides from buthids; (2) Scorpine-like peptides from Scorpionidae and Caraboctonidae species, including scorpine, Opiscorpines 1–4, HgeScplp1, HgeScplp2 and Heteroscorpine 1; (3) heterogeneous peptides similar to BmTXKβ of buthids and iurids [1,2,3,4,5].
The βSPN-type CS-α/β domain is more closely related to invertebrate defensins, antimicrobial peptides involved in the innate immune response of several invertebrate groups (see <PDOC00356>), than to the classical scorpion toxins. Its structure shows an α helix along with one β sheet stabilized by three disulfide bridges, folding into a CS-α/β motif (see <PDB:5IPO>). The connectivity between the ordinal numbered cysteines is C1-C4, C2-C5, and C3-C6 .
The profile we developed covers the entire βSPN-type CS-α/β domain.Last update:
April 2018 / First entry.
PROSITE method (with tools and information) covered by this documentation:
|1||Authors||Diego-Garcia E. Schwartz E.F. D'Suze G. Gonzalez S.A.R. Batista C.V.F. Garcia B.I. de la Vega R.C. Possani L.D.|
|Title||Wide phylogenetic distribution of Scorpine and long-chain beta-KTx-like peptides in scorpion venoms: identification of 'orphan' components.|
|2||Authors||Feng J. Yu C. Wang M. Li Z. Wu Y. Cao Z. Li W. He X. Han S.|
|Title||Expression and characterization of a novel scorpine-like peptide Ev37, from the scorpion Euscorpiops validus.|
|Source||Protein Expr. Purif. 88:127-133(2013).|
|3||Authors||Luna-Martinez K. Jimenez-Vargas J.M. Possani L.D.|
|Title||Scorpine-Like Peptides. Single Cell Biology 5(2016).|
|4||Authors||Zhu S. Gao B. Aumelas A. del Carmen Rodriguez M. Lanz-Mendoza H. Peigneur S. Diego-Garcia E. Martin-Eauclaire M.-F. Tytgat J. Possani L.D.|
|Title||MeuTXKbeta1, a scorpion venom-derived two-domain potassium channel toxin-like peptide with cytolytic activity.|
|Source||Biochim. Biophys. Acta 1804:872-883(2010).|
|5||Authors||Flores-Solis D. Toledano Y. Rodriguez-Lima O. Cano-Sanchez P. Ramirez-Cordero B.E. Landa A. Rodriguez de la Vega R.C. Del Rio-Portilla F.|
|Title||Solution structure and antiparasitic activity of scorpine-like peptides from Hoffmannihadrurus gertschi.|
|Source||FEBS Lett. 590:2286-2296(2016).|