利用转基因毕赤酵母高表达小分子药用多肽的研究

Over-expression of low-molecular weight medical peptide in transgenetic yeart Pichia pastoris

天然小肽Gsp有明显的降血糖功效 ,由 5 9个氨基酸残基组成。其编码基因由本实验室设计、合成 ,并重组构建成表达质粒 pPIC9 Gsp .经电穿孔将该质粒转化为毕赤酵母GS115 (His4 -mut+ ) ,挑选His+ muts 型菌株进行重组蛋白胞外表达研究。表达蛋白经Tricine SDS PAGE凝胶电泳分析确定了相对分子质量的正确性 ,其氨基酸测序显示与天然多肽序列一致 ,并经紫外扫描分析确定了表达量为 344mg/L左右。

The medical peptide(Gsp) mentioned in this article has potential function of declining blood sugar as a diabetes drug. It consists of 59 amino acid residues. A synthesized DNA fragment which contains the coding region of the peptide was inserted into plasmid pPIC9 to construct an over expression vector pPIC9 Gsp. After electroporation of Pichia pastoris (His4 - mut +), some transformants were picked up for the purpose of expression analysis by Tricine SDS PAGE and amino acids sequencing, etc. All of these proved that the expressed peptide has right structure and molecular weight as well as the expression can reach 344?mg/L.