| 摘要 |
PURPOSE:To enable the insertion of beneficial exogenous gene into a yeast cell, and the manifestation of the gene maintained stably in the yeast, by using a hybrid plasmid vector composed of the 2mumDNA sequence of a yeast and the DNA sequence originated from Escherichia coli, and capable of being maintained stably even in a host yeast (cir deg.) devoid of 2mumDNA. CONSTITUTION:The vector is a hybrid plasmid composed of the 2mumDNA sequence of a yeast and the DNA sequence originated from Escherichia coli, having a drug-resistant gene, and containing a DNA sequence incised with a restriction enzyme which cannot incise the 2mumDNA sequence and the DNA sequence originated from Escherichia coli. Accordingly, the vector can be converted to a plasmid vector capable of stably keeping a larger number of copies stably in a cir deg. host yeast by removing the E. coli-originated DNA with a proper restriction enzyme in a cloning vector obtained by introducing a beneficial exogenous gene (e.g. various immune-relating peptides) to the above vector. The transformed strain prepared by the use of the vector enables the production of the desired peptide in high efficiency. An example of the path for forming the hybrid plasmid is shown in the figure. |
