Isolation and Characterization of Conotoxin bt5a from Conus betulinus

AimTo study the chemical constituents of the venom of Conus betulinus that collected from South China Sea.MethodsGel chromatography and HPLC were applied to isolate toxins from the venom of Conus betulinus and a peptide toxin was obtained. Its chemical structure was characterized by mass spectrometry, amino acid analysis, N-terminal sequence and disulfide location. The structure was validated by comparison with natural and synthetic compounds.ResultsA conotoxin named conotoxin bt5a was isolated from the venom of Conus betulinus and its sequence is H-Ser-Gla-Cys-Cys-Ile-Arg-Asn-Phe-Leu-Cys-Cys-OH, in which Cys3 and Cys10, Cys4 and Cys11 form two intrachain disulfide bonds.ConclusionConotoxin bt5a is a new member of T-superfamily conotoxins.