cDNAs of barley α amylase and A.niger glucoamylase were cloned in one E.coli yeast shuttle plasmid resulting in the construction of expression secretion vector pMAG15. pMAG15 was transformed into S.cerevisiae GRF18 b...cDNAs of barley α amylase and A.niger glucoamylase were cloned in one E.coli yeast shuttle plasmid resulting in the construction of expression secretion vector pMAG15. pMAG15 was transformed into S.cerevisiae GRF18 by protoplast transformation. The barley α amylase and A.niger glucoamylase were efficiently expressed under the control of promoter and terminator of yeast PGK gene and their own signal sequence. Over 99% of the enzyme activity expressed was secreted to the medium. The recombinant yeast strain, S.cerevisiae GRF18(pMAG15), hydrolyzes 99% of the starch in YPS medium containing 15% starch in 47 h. The glucose produced can be used for the production of ethanol.展开更多
文摘cDNAs of barley α amylase and A.niger glucoamylase were cloned in one E.coli yeast shuttle plasmid resulting in the construction of expression secretion vector pMAG15. pMAG15 was transformed into S.cerevisiae GRF18 by protoplast transformation. The barley α amylase and A.niger glucoamylase were efficiently expressed under the control of promoter and terminator of yeast PGK gene and their own signal sequence. Over 99% of the enzyme activity expressed was secreted to the medium. The recombinant yeast strain, S.cerevisiae GRF18(pMAG15), hydrolyzes 99% of the starch in YPS medium containing 15% starch in 47 h. The glucose produced can be used for the production of ethanol.
