新芋螺毒素S03的活性与折叠的关系

利用O－超家族芋螺毒素具有保守信号肽编码序列的特性，采用RACE方法，对线纹芋螺O－超家族芋螺毒素的cDNA进行克隆、序列测定，并经化学合成，获得一种新型高活性芋螺多肽毒素SO3。该肽含25个氨基酸残基，其序列为CKAAGKPCSRIAYNCCTGSCRSGKC－NH2，有三对二硫键。对其进行了正确折叠及活性筛选。结果表明，该肽折叠主峰对小鼠脑内给药100ng，可明显观察到小鼠颤抖现象，对小鼠有明显的镇痛作用，而非正确折叠则无反应。

Research on the relationship between refolding and bioactivity of the new type of conotoxin SO3

Owing to the characterization that O-superfamily conotoxin has the sequence coded by conserved signal peptide, the cDNA of Conus striatus O-superfamily was cloned using the RACE method and was sequenced. The new type conotoxin SO3 was chemically synthesized; contains 25 amino acid, its sequence is CKAAGKPCSRIAYNCCTGSCRSGKC-NH 2, and has three disulfided bonds. Conotoxin SO3 was refolded and its bioactivity was tested. The results shows: Injecting 100ng of the major peak of the peptide to mice brain, the peptide can make the mice shivering and can ease mice pain, however, the peptides without correct refold haven't those bioactivity.