Advances of Red Recombination System in Escherichia coli Gene Modification

As a new recombination system,Red recombination has been widely used in E.coli gene knockout.Comparing with Rec recombination,Red recombination has the advantages of exploring short homologous arms and high recombination rate.The length of homologous arms usually are 36~60 nt.The function of Exo,Beta and Gam proteins in Red recombination,three kind of plasmids and their functions in E.coli gene knockout system were reviewed.The three kind of plasmids are plasmid which has exo,bet,gam for Red recombination,plasmid which has resistance tag and FRT site for PCR template and plasmid which has FLP recombinase for eliminating resistance tag.The concentration and inducing time of L-arabinose and the length of homologous arms by literature mining were summarized,and the optimal parameters was proposed.The optimal concentration and inducing time of L-arabinose are 100 mmol/L and 90 min,and the optimal length of homologous arms is 56 nt.