Construction ofl-Threonine Overproducing Strains ofEscherichia coliK-12 Using Recombinant DNA Techniques

Improvement of anl-Threonine Producer Derived fromBrevibacterium flavumUsing Threonine Operon ofEscherichia coliK-12

“…The thr operon of E. coli K-12 PIM4 was cut out from pAJ294 7 ) with BamHI and Sail, and inserted into Brevibacterium vector pAJ220, as shown in Fig. I.…”

Improvement of the Stability of Recombinant Plasmids Carrying the Threonine Operon in anl-Threonine-hyperproducing Strain ofEscherichia coliW

“…Recently, Khourges et al S ) and Miwa et al 6 ) employed recombinant DNA techniques successfully to increase L-threonine productivity through the amplification of the E. coli thr operon.…”