title: Solution structure of native and recombinant expressed toxin CssII from the venom of the scorpion Centruroides suffusus suffusus, and their effects on Nav1.5 sodium channels.
abstract: The three-dimensional structures of the long-chain mammalian scorpion β-toxin CssII from Centruroides suffusus suffusus and of its recombinant form, HisrCssII, were determined by NMR. The neurotoxin CssII (nCssII) is a 66 amino acid long peptide with four disulfide bridges; it is the most abundant and deadly toxin from the venom of this scorpion. Both native and recombinant CssII structures were determined by nuclear magnetic resonance using a total of 828 sequential distance constraints derived from the volume integration of the cross peaks observed in 2D NOESY spectra. Both nCssII and HisrCssII structures display a mixed α/β fold stabilized by four disulfide bridges formed between pairs of cysteines: C1-C8, C2-C5, C3-C6, and C4-C7 (the numbers indicate the relative positions of the cysteine residues in the primary structure), with a distortion induced by two cis-prolines in its C-terminal part. The native CssII electrostatic surface was compared to both the recombinant one and to the Cn2 toxin, from the scorpion Centruroides noxius, which is also toxic to mammals. Structural features such N- and C-terminal differences could influence toxin specificity and affinity towards isoforms of different sub-types of Na(v) channels.
authors.affiliation: Departamento de Química de Biomacromoléculas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico.
authors.forename: Alma L
authors.initials: AL
authors.lastname: Saucedo
authors.forename: Federico
authors.initials: F
authors.lastname: del Rio-Portilla
authors.forename: Cristiana
authors.initials: C
authors.lastname: Picco
authors.forename: Georgina
authors.initials: G
authors.lastname: Estrada
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Prestipino
authors.forename: Lourival D
authors.initials: LD
authors.lastname: Possani
authors.forename: Muriel
authors.initials: M
authors.lastname: Delepierre
authors.forename: Gerardo
authors.initials: G
authors.lastname: Corzo
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003545:Cysteine / Q000737:chemistry; D004220:Disulfides; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D062554:NAV1.5 Voltage-Gated Sodium Channel / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009498:Neurotoxins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D018408:Patch-Clamp Techniques; D011392:Proline / Q000737:chemistry; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D012604:Scorpion Venoms / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000633:toxicity; D012605:Scorpions / Q000737:chemistry* / Q000472:pathogenicity; D012996:Solutions; D055672:Static Electricity; D014162:Transfection
chemical_list: D004220:Disulfides; D062554:NAV1.5 Voltage-Gated Sodium Channel; D009498:Neurotoxins; D011994:Recombinant Proteins; D012604:Scorpion Venoms; D012996:Solutions; C066386:scorpion toxin Css II; D011392:Proline; D003545:Cysteine