摘要: Publisher Summary Bacteriophages are viruses that multiply exclusively inside bacterial cells. In natural environments, bacteriophages form relatively stable associations with bacteria, called lysogenic carry the virus intracellularly, but resistant to its lytic action. Extracellular originates by lysis of exceptional cells in cultures. Genetic experiments bacteriophage call for one or more stocks phage and suitable hosts. A stock consists simply products a sensitive culture infected from recently started clone. It may contain anywhere 10 9 I2 particles per milliliter. The hosts required strain, used propagation titration virus, indicator strains selectively certain their identification. series dissimilar T1 (Type 1), T2 T7 all lysing single strain Escherichia coli known as B, have been recent genetic experiments. Among these, only T4 intensively studied. These related viruses, large size, which possess morphologically functionally differentiated structure.