A conditional knockout-rescue system was developed to construct an in-frame deletion strain of Escherichia coli essential genes. The target was flanked with marker genes and FRT (FLP recognition target) sites. and a plasmid containing arabinose-induced FLP recombinase was transformed. After arabinose induction. https://www.ashleyshomestores.shop/product-category/7-piece-counter-dining-set/