title: A K⁺ channel blocking peptide from the Cuban scorpion Rhopalurus garridoi.
abstract: A proteomic analysis of the venom obtained from the Cuban scorpion Rhopalurus garridoi was performed. Venom was obtained by electrical stimulation, separated by high performance liquid chromatography, and the molecular masses of their 50 protein components were identified by mass spectrometry. A peptide of 3940 Da molecular mass was obtained in pure form and its primary structure determined. It contains 37 amino acid residues, including three disulfide bridges. Electrophysiological experiments showed that this peptide is capable of blocking reversibly K(+)-channels hKv1.1 with a Kd close to 1 μM, but is not effective against hKv1.4, hERG1 and EAG currents, at the same concentration. This is the first protein component ever isolated from this species of scorpion and was assigned the systematic number α-KTx 2.14.
authors: Center for Mountain Development, Ministry of Science, Technology and, Environment, Limonar de Monte Roux, El Salvador Guantánamo, Cuba. Electronic address: rodolfo@cdm.gtmo.inf.cu.
authors: Rodolfo
authors: R
authors: Rodríguez-Ravelo
authors: Department of Molecular Medicine and Bioprocesses, Biotechnology, Institute, National Autonomous University of Mexico, Avenida Universidad 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca, Morelos 62210, Mexico. Electronic address: rita@ibt.unam.mx.
authors: Rita
authors: R
authors: Restano-Cassulini
authors: Department of Molecular Medicine and Bioprocesses, Biotechnology, Institute, National Autonomous University of Mexico, Avenida Universidad 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca, Morelos 62210, Mexico. Electronic address: zam@ibt.unam.mx.
authors: Fernando Z
authors: FZ
authors: Zamudio
authors: Department of Molecular Medicine and Bioprocesses, Biotechnology, Institute, National Autonomous University of Mexico, Avenida Universidad 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca, Morelos 62210, Mexico. Electronic address: fredy@ibt.unam.mx.
authors: Fredy I V
authors: FI
authors: Coronas
authors: Department of Biochemistry, School of Biology, University of Havana, Havana, Cuba. Electronic address: georgina@fbio.uh.cu.
authors: Georgina
authors: G
authors: Espinosa-López
authors: Department of Molecular Medicine and Bioprocesses, Biotechnology, Institute, National Autonomous University of Mexico, Avenida Universidad 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca, Morelos 62210, Mexico. Electronic address: possani@ibt.unam.mx.
authors: Lourival D
authors: LD
authors: Possani
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004594:Electrophysiology; D013058:Mass Spectrometry; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D026902:Potassium Channel Blockers / Q000737:chemistry* / Q000378:metabolism / Q000493:pharmacokinetics; D015221:Potassium Channels / Q000187:drug effects; D040901:Proteomics; D012604:Scorpion Venoms / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D012605:Scorpions / Q000378:metabolism*
chemical_list: D010455:Peptides; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D012604:Scorpion Venoms
keywords: Amino acid sequence; K(+)-channel; Proteome; Rhopalurus garridoi; Scorpion venom