title: Structure of the O-glycosylated conopeptide CcTx from Conus consors venom.
abstract: The glycopeptide CcTx, isolated from the venom of the piscivorous cone snail Conus consors, belongs to the κA-family of conopeptides. These toxins elicit excitotoxic responses in the prey by acting on voltage-gated sodium channels. The structure of CcTx, a first in the κA-family, has been determined by high-resolution NMR spectroscopy together with the analysis of its O-glycan at Ser7. A new type of glycopeptide O-glycan core structure, here registered as core type 9, containing two terminal L-galactose units {α-L-Galp-(1→4)-α-D-GlcpNAc-(1→6)-[α-L-Galp-(1→2)-β-D-Galp-(1→3)-]α-D-GalpNAc-(1→O)}, is highlighted. A sequence comparison to other putative members of the κA-family suggests that O-linked glycosylation might be more common than previously thought. This observation alone underlines the requirement for more careful and in-depth investigations into this type of post-translational modification in conotoxins.
authors.affiliation: NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands. h.hocking@tum.de
authors.forename: Henry G
authors.initials: HG
authors.lastname: Hocking
authors.forename: Gerrit J
authors.initials: GJ
authors.lastname: Gerwig
authors.forename: Sébastien
authors.initials: S
authors.lastname: Dutertre
authors.forename: Aude
authors.initials: A
authors.lastname: Violette
authors.forename: Philipe
authors.initials: P
authors.lastname: Favreau
authors.forename: Reto
authors.initials: R
authors.lastname: Stöcklin
authors.forename: Johannis P
authors.initials: JP
authors.lastname: Kamerling
authors.forename: Rolf
authors.initials: R
authors.lastname: Boelens
mesh_terms: D000818:Animals; D052078:Conus Snail / Q000737:chemistry*; D006020:Glycopeptides / Q000737:chemistry*; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D008978:Mollusk Venoms / Q000737:chemistry*
chemical_list: D006020:Glycopeptides; D008978:Mollusk Venoms