利用转基因毕赤酵母高表达小分子药用多肽的研究

天然小肽Gsp有明显的降血糖功效,由59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.

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

The medical peptide (Gsp) mentioned in this article has potential function of declining blood sugar as a diabetes drug. It consist s 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.