here is part of my intro...
The viruses that infect bacteria are known as bacteriophages, development of the one-step growth experiment by Max Delbruch and Emory Ellis in 1939 marks the beginning of modern bacteriophage research. (Prescott et al 2002). Pseudomonas aeruginosa phage E79 is virulent and has double stranded DNA with a molecular weight of 120 x 10, transducing phage capable of transferring this amount of bacterial chromosome would be of value in elaborating the P. aeruginosa genetic map. (Morgan, 1979)