A plasmid-free recombinant strain of Escherichia coli with constitutive aspartase activity and a method for the synthesis of L-aspartic acid using this strain as a biocatalyst

摘要

FIELD: biotechnology.SUBSTANCE: plasmid-free recombinant Escherichia coli strain with constitutive aspartic activity and obtained by replacing the promoter of the aspA gene in Escherichia coli strain MG1655 with the bacteriophage T5 pG25 promoter is represented. A method for L-aspartic acid synthesis from ammonium fumarate is provided, using the said recombinant strain as a biocatalyst in the form of either free or immobilized cells.EFFECT: more efficient preparation of L-aspartic acid; and allows to reduce the time of its production 3-4 times due to higher aspartic activity of the biocatalyst.2 cl, 1 tbl, 3 ex