Disulfide bridges and blockage of Shaker B K(+)-channels by another butantoxin peptide purified from the Argentinean scorpion Tityus trivittatus.
A peptide was isolated from the venom of the scorpion Tityus trivittatus. It is an isoform of the toxin TsTX-IV earlier described [Toxicon 37 (1999) 651] and identical to butantoxin [Arch. Biochem. Biophys. 379 (2000) 18], both isolated from the Brazilian scorpion Tityus serrulatus. This newly characterized peptide contains 40 amino acid residues with a molecular mass of [M+H(+)] 4507.0, cross-linked by four disulfide bridges, made between the cysteine pairs: Cys2-Cys5, Cys10-Cys31, Cys16-Cys36 and Cys20-Cys38. It blocks in a completely reversible manner the Shaker B K(+)-channels, with a K(d) around 660nM. It belongs to the sub-family 12 and it is now being classified as alpha-KTx 12.2.
Coronas
Fredy V
FV
Department of Molecular Recognition and Structural Biology, Institute of Biotechnology, National Autonomous University of Mexico, Cuernavaca, Mexico.
de Roodt
Adolfo R
AR
Portugal
Timoteo Olamendi
TO
Zamudio
Fernando Z
FZ
Batista
Cesar V F
CV
Gómez-Lagunas
Froylan
F
Possani
Lourival D
LD
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004220:Disulfides / Q000737:chemistry*; D008969:Molecular Sequence Data; D009498:Neurotoxins / Q000737:chemistry* / Q000494:pharmacology; D010455:Peptides; D026902:Potassium Channel Blockers / Q000737:chemistry* / Q000494:pharmacology; D015221:Potassium Channels / Q000187:drug effects / Q000378:metabolism; D020033:Protein Isoforms; D012604:Scorpion Venoms / Q000737:chemistry* / Q000494:pharmacology; D051637:Shaker Superfamily of Potassium Channels
D004220:Disulfides; D009498:Neurotoxins; D010455:Peptides; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D020033:Protein Isoforms; D012604:Scorpion Venoms; D051637:Shaker Superfamily of Potassium Channels; C411251:butantoxin; C119251:tityustoxin IV