Recall that cyanobacteria may have developed as a result of transfer of genetic material: a bacterium carrying the genetic information for one photosystem received (from another bacterium) the genetic information for a second, distinct photosystem. what might be possible mechanisms of action for genetic transfer?

The possible mechanism of action in this situation are three. The bacteria could have taken up the genettic information from their surroundings. The bacteria could exchange genetic information through development of cytoplasmic connections. And lastly, the bacteria might become infected by a virus that carries information of the genes taken from previously infected bacteria.

This genetic transfer can be one of these three mechanism in bacteria:

Transduction:  It is the process by which foreign DNA is introduced into a cell by a virus or viral vector.Conjugation:  In this mechanism the donor bacterium transfers DNA to the recipient by mating.Transformation:  In this mechanism the recipient bacterium takes up extracellular donor DNA.