Requirement of protein synthesis for bacteriophage phi X174 superinfection exclusion.

Within 5 to 10 min at 37 C, bacteria infected by bacteriophage phiX174 acquire the ability to exclude superinfecting phiX particles from reproducing themselves. The superinfecting phage are blocked at a stage prior to synthesis of the parental replicative form molecule; the superinfecting deoxyribonucleic acid remains as intact (infective) single strands. Establishment of superinfection exclusion and its maintenance require protein synthesis.