J. Lederberg and Edward L Tatum demonstrated conjugation in E. coil in the year 1946. In this method of gene transfer the donor cell gets attached to the recipient cell with the help of pili.
The pilus grows in size and forms the conjugation tube. The plasmid of donor cell which has the F+ (fertility factor) undergoes replication. Only one strand of DNA is transferred to the recipient cell through conjugation tube. The recipient completes the structure of double stranded DNA by synthesizing the strand that complements the strand acquired from the donor.
