JM109 Competent Cells

JM109 is a K strain that is recA– and endA– to minimize recombination and improve the quality of plasmid DNA. In addition, the cells carry the F´ episome, which allows blue/white screening. JM109 Competent Cells are available for convenient transformation in two efficiencies: High Efficiency at greater than 10⁸cfu/μg for Cloning and Single Use, and Subcloning Efficiency at greater than 10⁷cfu/μg.

For researchers doing more than one transformation, competent cells are available in standard format (200µl aliquots). For added convenience, single-use competent cells (50µl aliquots) also are offered.

JM109 Competent Cells are prepared according to a modified procedure of Hanahan.

JM109 Genotype: endA1, recA1, gyrA96, thi, hsdR17 (r_k^–, m_k⁺), relA1, supE44, Δ( lac-proAB), [F´ traD36, proAB, laqI^qZΔM15].

Reference

1. Hanahan, D. (1985) DNA Cloning, Vol. 1, Glover, D., ed., IRL Press, Ltd., 109.