METHOD FOR MAINTAINING FOREIGN GENE IN CELL STABLY

摘要

A method for preparing a protein or peptide encoded by a foreign gene by expressing a foreign gene, which comprises the steps of: preparing a recombinant vector comprising in an expressible state a gene encoding an aminoacyl-tRNA synthetase, in which a desired foreign gene has been inserted in an expressible state; preparing a mutant host cell or the like in which a chromosomal gene encoding an aminoacyl-tRNA synthetase has been knocked out; transforming the mutant host cell with the recombinant vector to obtain a transformant; and culturing the transformant to prepare the protein or peptide encoded by the foreign gene. It becomes possible to provide a novel means for permitting the retention of a recombinant DNA cloning vector without employing an antibiotic and without limiting the composition of the medium; and a method for preparing a protein or peptide encoded by a foreign gene by using the means.