RECOMBINANT PLASMID, AND PREPARATION OF TRANSFORMED YEAST AND ALPHA-AMYLASE USING THEREOF

摘要

PURPOSE:To produce a large amount of alpha-amylase having the same enzymogical activity as the human-originated alpha-amylase, by treating a yeast with a recombinant plasmid integrated with an alpha-amylase gene, and culturing the resulting transformed yeast. CONSTITUTION:A plasmid vector containing the gene of yeast as well as the gene of Escherichia coli and carrying the fraction to control the manifestation of the suppressive acidic phostaphase activity of the yeast is incised with a restriction enzyme against the linker used in the vector under the control with said phostaphase-promoter. The product is linked with the human-originated alpha- amylase DNA to obtain a recombinant plasmid integrated with alpha-amylase gene. A yeast [e.g. Saccharomyces cerevisiae AH22a leu2 his4 Cav/(Cir<+>)] is transformed with said recombinant plasmid, and the obtained transformed yeast is cultured first in a medium containing phosphoric acid, and then in a medium free from phosphoric acid.