一种新型独特芋螺毒素的分离与结构鉴定

Isolation and Structure Characterization of a New T-Superfamily Conotoxin from Conus Caracteristicus

Cone snails are tropical marine predatory molluscs,and there is an unprecedented variety of neuropharmacologically active peptide.Over seventy living species of cone snails are distributed in China.The ve-nom of Conus caracteristicus collected from South China Sea was studied in this work.A new conotoxin,cr5a,was isolated from the venom through Sephadex G-25 chromatography and HPLC,and then was identified by（amino） acid analysis,mass spectrometry,N-terminal sequence.The primary structure of cr5a was CCKFQFLNFCCNE,it shared a conserved T-superfamily of conotoxins arrangement of cysteine residues（CC-CC）.Total chemical synthesis of the two possible disulfide linkages of cr5a was achieved,and the result of HPLC co-elution showed that cr5a was a tridecapeptide with a disulfide connectivity of Cys1-Cys10, Cys2-Cys11.So cr5a is a new member of the T-superfamily conotoxins.

Cone snails are tropical marine predatory molluscs, and there is an unprecedented variety of neuropharmacologically active peptide. Over seventy living species of cone snails are distributed in China. The venom of Conus caracteristicus collected from South China Sea was studied in this work. A new conotoxin, crSa, was isolated from the venom through Sephadex G-25 chromatography and HPLC, and then was identified by amino acid analysis, mass spectrometry, N-terminal sequence. The primary structure of crSa was CCKFQFLNFCCNE, it shared a conserved T-superfamily of conotoxins arrangement of cysteine residues （CC-CC）. Total chemical synthesis of the two possible disulfide linkages of cr5a was achieved, and the result of HPLC co-elution showed that cr5a was a tridecapeptide with a disulfide connectivity of Cys^1-Cys^10, Cys^2-Cys^11. So cr5a is a new member of the T-superfamily conotoxins.