马氏钳蝎蝎毒短肽BmK622的分离纯化和一级结构测定

应用凝胶过滤、离子交换和HPLC反相色谱法从马氏蝎粗毒中分离纯化得到蝎毒 多肽BmK622．联合运用串联质谱法和Edman降解法，鉴定了KmK622N端19个残基的序 列，经过数据库检索，发现数据库中用cDNA克隆方法鉴定了序列的马氏钳蝎蝎毒短 肽BmTX3一级序列N端19个残基与BmK622已测定的N端19个残基序列完全相同， BmK622的分子量测定和氨基酸组成分折的结果表明，BmK22与BmTX3分子量相同、氨 基酸组成一致，从而BmK22的一级结构为：GFLID VKCFA SSECW TACKK VTGSG QGKCQ NNQCR CY．

Purification and Primary Structure of a Toxin-like Peptide BmK622 from the Venom of Chinese Scorpion Buthus martensii Karsch

The toxin like peptide BmK622 has been purified from the venom of the Chinese scorpion Buthus martensii Karsch by using combined gel filtration, ion exchange and reversed phase chromatography techniques. The sequence of the peptide BmK622 was determined by the hybrid applying of tandem CID MS/MS, Edman degradation and database searching. Firstly the sequence for the N terminal 19 amino acids of BmK622 was obtained by using tandem CID MS/MS and Edman degradation. The following database searching revealed a hit. The sequence of N terminal 19 amino acid residues of BmK622 is identical with that of the scorpion toxin BmTX3, which was determined by cDNA cloning. In addition, the molecular weight and the amino acid compositions of BmK622 are consistent with the calculated values according to the sequence of BmTX3. All these data suggested that BmK622 shared the same primary structure with BmTX3, and the intact sequence of BmK622 is as follows: FGLID VKCFA SSECW TACKK VTGSG QGKCQ NNQCR CY.