Characterization of a Novel Conus bandanus Conopeptide Belonging to the M-Superfamily Containing Bromotryptophan
Bao Nguyen,
Jean-Pierre Le Caer,
Gilles Mourier,
Robert Thai,
Hung Lamthanh,
Denis Servent,
Evelyne Benoit,
Jordi Molgó
Affiliations
Bao Nguyen
Neurobiology and Development Laboratory, Research Unit # 3294, Institute of Neurobiology Alfred Fessard # 2118, National Center for Scientific Research, Gif sur Yvette Cedex 91198, France
Jean-Pierre Le Caer
Research Unit # 2301, Natural Product Chemistry Institute, National Center for Scientific Research, Gif sur Yvette Cedex 91198, France
Gilles Mourier
Molecular Engineering of Proteins, Institute of Biology and Technology Saclay, Atomic Energy Commission, Gif sur Yvette Cedex 91191, France
Robert Thai
Molecular Engineering of Proteins, Institute of Biology and Technology Saclay, Atomic Energy Commission, Gif sur Yvette Cedex 91191, France
Hung Lamthanh
Neurobiology and Development Laboratory, Research Unit # 3294, Institute of Neurobiology Alfred Fessard # 2118, National Center for Scientific Research, Gif sur Yvette Cedex 91198, France
Denis Servent
Molecular Engineering of Proteins, Institute of Biology and Technology Saclay, Atomic Energy Commission, Gif sur Yvette Cedex 91191, France
Evelyne Benoit
Neurobiology and Development Laboratory, Research Unit # 3294, Institute of Neurobiology Alfred Fessard # 2118, National Center for Scientific Research, Gif sur Yvette Cedex 91198, France
Jordi Molgó
Neurobiology and Development Laboratory, Research Unit # 3294, Institute of Neurobiology Alfred Fessard # 2118, National Center for Scientific Research, Gif sur Yvette Cedex 91198, France
A novel conotoxin (conopeptide) was biochemically characterized from the crude venom of the molluscivorous marine snail, Conus bandanus (Hwass in Bruguière, 1792), collected in the south-central coast of Vietnam. The peptide was identified by screening bromotryptophan from chromatographic fractions of the crude venom. Tandem mass spectrometry techniques were used to detect and localize different post-translational modifications (PTMs) present in the BnIIID conopeptide. The sequence was confirmed by Edman’s degradation and mass spectrometry revealing that the purified BnIIID conopeptide had 15 amino acid residues, with six cysteines at positions 1, 2, 7, 11, 13, and 14, and three PTMs: bromotryptophan, γ-carboxy glutamate, and amidated aspartic acid, at positions “4”, “5”, and “15”, respectively. The BnIIID peptide was synthesized for comparison with the native peptide. Homology comparison with conopeptides having the III-cysteine framework (–CCx1x2x3x4Cx1x2x3Cx1CC–) revealed that BnIIID belongs to the M-1 family of conotoxins. This is the first report of a member of the M-superfamily containing bromotryptophan as PTM.
