Genomic engineering of Escherichia coli by the phage attachment site-based integration system with mutant loxP sites

► Bypass the plasmid-incurred problems by insertion of genes. ► Circumvent the genomic rearrangement event by using loxP mutant sites. ► Create additional phage attachment attB sites for unlimited integration of genes. ► Reconstruct the heterologous n-butanol pathway in E. coli free of plasmids. ► Multiple insertion of the exoglucanase gene in E. coli.