E. Coli reproduce by binary fission and conjugation (“the transfer of genetic material through a sex pilus”).
The most prevalent reproduction for E. Coli is asexual reproduction which takes place when the E. Coli is undergoing binary fission. This type of reproduction begins with the replication of one DNA molecule. Secondly, the copies of the genetic material attach themselves to the cell membrane. Thirdly, when the bacterium’s size has doubled from its original size, the cell membrane starts pinching inward. Fourtly, between the two DNA molecules, a cell wall is produced. Lastly, the cell wall divides the cell into two daughter cells.
E. Coli can also go through a second process of reproduction known as conjugation. Conjugation is a reproduction process which involves the transferring of genetic material by the sex pili between two bacteria. Chiefly, one has to take in consideration that this is not a sexual reproduction because there is no combination of in the gametes. The reproduction process of conjugation starts with the E. Coli that have a plasmid, where the genome is replicated. Once the E. coli has finished replicating its genetic material, it is now called a “donor.” Interestingly, the E. coli’s enzyme can now send signals to show that it’s ready to mate. Once a mate is found, the donor attaches itself to the sex pilus of its mate. By doing so, the donor transfers the plasmid.
Source: [bilingualbiology10.blogspot.com ]
More information on the reproduction process of conjugation