An improved method for deleting large regions of Escherichia coli K-12 chromosome using a combination of Cre/loxP and lambda Red.

We have established an improved large deletion method in Escherichia coli genome using a combination of two different recombination systems, lambda Red and Cre/loxP. The loxP site could be rapidly and efficiently integrated in the genome by lambda Red and large deletions of both 117- and 165-kbp regions could be generated in 100% efficiency by Cre/loxP. Comparative genomic hybridization microarray experiments of deletion strains indicated that deletions were generated only in expected regions of the genome. These results have demonstrated that the method is useful for genome engineering in E. coli. Copyright 2004 Federation of European Microbiological Societies