DH5-Alpha Cells are E. coli cells engineered by American biologist Douglas Hanahan to maximize transformation efficiency.
They are defined by three[1] mutations: recA1, endA1 which help plasmid insertion and lacZΔM15 which enables blue white screening.
The cells are competent and often used 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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