Читать книгу Snyder and Champness Molecular Genetics of Bacteria - Tina M. Henkin - Страница 32

Selection of rare strains of a phage is possible; as with bacteria, it requires conditions under which only the desired phage strain can multiply to form a plaque. For phages, these selective conditions may be a bacterial host in which only the desired strain can multiply or a temperature at which only the phage strain being selected can multiply. Note that the bacterial host must be able to multiply under the same selective conditions; otherwise, a plaque cannot form.

As with bacteria, selections allow the isolation of very rare strains or mutants. If selective conditions can be found for the strain, mill ions of phages can be mixed with the bacterial host, and only the desired strain multiplies to form a plaque. A pure strain can then be obtained by picking the phage from the plaque and purifying the phage strain under the same selective conditions.