XL-1 cells are tetracycline resistant. XL1-Blue cells are endonuclease (endA) deficient, which greatly improves the quality of miniprep DNA, and are recombination (recA) deficient, improving insert stability. The hsdR mutation prevents the cleavage of cloned DNA by the EcoK endonuclease system. The lacIq Z∆M15 gene on the F´ episome allows blue-white color screening.
Introduction
Strains Resistance tetracycline
Culture Medium LB
Condition 37℃ ,under the aerobic conditions
The XL1-Blue strain allows blue-white color screening for recombinant plasmids and is an excellent host strain for routine cloning applications using plasmid or lambda vectors.
Genotype
XL1-Blue Genotype: recA1 endA1 gyrA96 thi-1 hsdR17 supE44 relA1 lac [F´ proAB lacIq Z∆M15 Tn10 (Tetr )]. (Genes listed signify mutant alleles. Genes on the F´ episome, however, are wild-type unless indicated otherwise).
