XL2-blue MRF’ Ultracompetent Cells
The XL2-blue MRF´ (Minus Restriction) strain is deficient in all known restriction systems, preventing cleavage of cloned DNA that carries cytosine and/or adenine methylation (often present in eukaryotic DNA and cDNA). These restriction-minus cells are endonuclease deficient, for improved miniprep DNA quality, and recombination deficient, for greater insert stability.
Transformation efficiency is ≥ 5 x 109 transformants/µg of pUC18 DNA. Cells are resistant to tetracycline and chloramphenicol and allow blue-white screening for recombinant plasmids.