DH5-Alpha Cell

DH5-Alpha Cells are engineered E.coli cells in order to maximize transformation efficiency. They are given their name from Douglas Hanahan an American biologist. The cells are defined by three mutations recA1, endA1 which help plasmid insertion and lacZM15 which enable blue white screening. The cells are competent and often use with calcium chloride transformation to insert the desired plasmid. A study of four transformation methods and six bacteria strains showed that the most efficient one was the DH5 strain with the Hanahan method

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