title: A biologically active hydrophobic T-1-conotoxin from the venom of Conus spurius.
abstract: A major, very hydrophobic peptide, sr5a, was purified from the venom duct of Conus spurius specimens collected in the Yucatan Channel, Mexico. Its amino acid sequence (IINWCCLIFYQCC; calculated monoisotopic mass assuming two disulfide bridges 1616.68 Da) was determined by automatic Edman degradation after reduction and alkylation, and confirmed by mass spectrometry (ESI monoisotopic mass, 1616.60; MALDI monoisotopic mass 1616.42 Da). The primary structure of sr5a showed the pattern that characterizes the family of the T-1-conotoxins, which belong to the T-superfamily of conotoxins. The disulfide bonds were determined by partial reduction and alkylation with N-ethylmaleimide, followed by total reduction and alkylation with 4-vinylpyridine, and automatic Edman sequencing. The connectivity of the Cys residues (I-III, II-IV) is the same as that found in the T-1-conotoxin family. When injected intracranially (2.0 nmol) into mice, peptide sr5a caused depressed behavioral activity.
authors.affiliation: Laboratory of Marine Neuropharmacology, Institute of Neurobiology, Universidad Nacional Autónoma de México, Campus UNAM-UAQ Juriquilla, Km 15 Carr. Querétaro-S.L.P., Juriquilla, Qro. 76230, México. maguilar@servidor.unam.mx
authors.forename: Manuel B
authors.initials: MB
authors.lastname: Aguilar
authors.forename: Leticia
authors.initials: L
authors.lastname: Lezama-Monfil
authors.forename: María
authors.initials: M
authors.lastname: Maillo
authors.forename: Heriberto
authors.initials: H
authors.lastname: Pedraza-Lara
authors.forename: Estuardo
authors.initials: E
authors.lastname: López-Vera
authors.forename: Edgar P
authors.initials: EP
authors.lastname: Heimer de la Cotera
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D020916:Conotoxins / Q000302:isolation & purification* / Q000494:pharmacology; D052078:Conus Snail / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D051379:Mice; D008970:Molecular Weight; D008978:Mollusk Venoms / Q000737:chemistry; D009043:Motor Activity / Q000187:drug effects; D010456:Peptides, Cyclic / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D020916:Conotoxins; D008978:Mollusk Venoms; D010456:Peptides, Cyclic