THE ISOLATION OF BACTERIOPHAGE

Abstract

This chapter reviews the isolation of bacteriophage. Bacteriophage capable of infecting a particular species of bacterium would most likely be found in an environment capable of supporting the growth of the host bacterium. In the streak plate method, the presence of phage is shown by clear areas caused by lysis of the growing cells of Escherichia Coli (E.Coli). to isolate a pure phage culture from plaques, material from a plaque can be transferred with a sterile needle to a young broth culture of E. coli, and the culture incubated until clearing occurs. It is advisable at the same time to incubate a broth culture of E. coli not infected with phage as a control as sometimes complete clearing will not occur because of the presence and subsequent development of phage-resistant mutants. In such cases, noticeably less turbidity in the case of the inoculated culture can be taken as indicative of the presence of phage.