Gene-transfer processes in bacteria

(a) Conjugation. A single DNA strand transferred during DNA replication in the donor is used to replicate a second strand in the recipient. Subsequent crossing over recombines DNA to form the exconjugant cell. (b) Transformation. A single strand of donor DNA taken across the membrane of the recipient cell recombines with recipient DNA to form the transformant cell. (c) Transduction. A donor DNA fragment encapsulated in a transducing phage is injected into the recipient cell, where it recombines to form the transductant cell(a) Conjugation. A single DNA strand transferred during DNA replication in the donor is used to replicate a second strand in the recipient. Subsequent crossing over recombines DNA to form the exconjugant cell. (b) Transformation. A single strand of donor DNA taken across the membrane of the recipient cell recombines with recipient DNA to form the transformant cell. (c) Transduction. A donor DNA fragment encapsulated in a transducing phage is injected into the recipient cell, where it recombines to form the transductant cell

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