A mating bridge, also known as a "conjugation bridge", is a connection between two bacterial cells that provides a passage way for DNA in bacterial conjugation.
A mating bridge is different from a sex pilus, which is a structure made by an F+ strain bacterium in bacterial conjugation. The pili (plural) act as attachment sites that promote the binding of bacteria to each other. In this way, an F+ strain makes physical contact with an F− strain. Once contact is made, the pili shorten and thereby draw the donor and recipient cells closer together. A conjugation bridge is then formed between the two cells, which provides a passageway for DNA transfer.
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