论文部分内容阅读
目的从中国南海堂皇芋螺(Conus imperialis)中克隆出新的芋螺毒素序列并用化学方法合成该毒素。方法根据A超家族保守的信号肽序列设计引物,采用cDNA的3’端快速扩增方法(3’RACE),从芋螺毒腺管中克隆出新的毒素基因。固相法合成线性多肽,折叠形成目标产物,用两步氧化折叠法测定多肽的二硫键连接方式。结果发现一种新的α-芋螺毒素cDNA序列Im1.6,其编码的成熟肽序列为GCCDIPDCYNKNREQC-NH2,二硫键连接方式为“C1-C3,C2-C4”。结论 Im1.6是一种新的α4/7型芋螺毒素,其氨基酸序列与报道的α-芋螺毒素显著不同。
Objective To clone a new conotoxin sequence from Conus imperialis and synthesize the toxin by chemical method. Methods Based on the conserved signal peptide sequence of superfamily A, a pair of primers were designed and a new toxin gene was cloned from the concentric duct of the genus Taro using the 3 ’rapid amplification of cDNA (3’RACE). The linear peptide was synthesized by solid phase method and folded to form the target product. The two - step oxidative folding method was used to determine the disulfide bond of the polypeptide. As a result, a novel α-conotoxin cDNA sequence Im1.6 was found which encoded the mature peptide sequence GCCDIPDCYNKNREQC-NH2 and the disulfide linkage was “C1-C3, C2-C4”. Conclusion Im1.6 is a novel α4 / 7 conotoxin with a significantly different amino acid sequence from the reported α-conotoxin.