去B链羧端七肽人胰岛素的分离纯化及性质研究

Purification and Characterization of Des heptapeptide of C terminal(B24 30)Human Insulin

在大肠杆菌温度诱导体系中以非融合方式进行去Ｂ链羧端七肽人胰岛素原基因的表达，获得去Ｂ链羧端七肽人胰岛素原，表达产物占细胞总蛋白量的１３％，表达产物经ＳｅｐｈａｄｅｘＧ－５０柱层析分离及胰蛋白酶和羧肽酶Ｂ的酶促转化等步骤，可得到纯度达９４％以上的去Ｂ链羧端七肽人胰岛素，其氨基酸组成与预期值相符，受体活性是标准猪胰岛素的１％．

Des heptapeptide of C terminal(B24 30)Human proinsulin gene was recombinated to the expression vector pBV220 and expressed in E.coli, induced by temperature.The expression level accounted for 13% of total bacterial proteins.After denaturation and renaturation,the expression product was purified by Sephadex G 50 gel filtration and converted to Des heptapeptide of C terminal(B24 30)human insulin by trypsin and carboxypeptidase B.Des heptapeptide of C terminal(B24 30)human insulin,purified by DEAE Sepharose Fast Flow,had an expected amino acid composition.The receptor binding activity was 1% as compared with standard porcine insulin.