| 摘要 |
PURPOSE:To provide a plasmid having remarkably improved production efficiency of tryptophan synthetase, by combining a DNA fragment containing a gene controlling the biosynthesis of tryptophan synthetase with particular two kinds of DNA fragments. CONSTITUTION:A plasmid proliferative autonomously in the cell of Escherichia coli can be produced by combining (A) a DNA fragment containing the gene controlling the biosynthesis of tryptophan synthetase (especially a DNA fragment obtained by bonding trp A and trp B fragments originated from tryptophan operon with a DNA fragment having the function of promoter capable of generating the above two genes and a DNA fragment having said promoter function), (B) a DNA fragment containing the gene controlling the proliferation controlling and distributing system and originated from an F-factor plasmid, and (C) a DNA fragment containing a gene controlling the autonomous proliferativity and originated from ColE1-plasmid. |
