Metabolic engineering of Escherichia coli BL21 strain using simplified CRISPR-Cas9 and asymmetric homology arms recombineering.

Background: The recent CRISPR-Cas coupled with λ recombinase mediated genome recombineering has become a common laboratory practice to modify bacterial genomes. It requires supplying a template DNA with homology arms for precise genome editing. However, generation of homology arms is a time-consuming, costly and inefficient process that is often overlooked.