[Genetic and phenogenetic study of the ts-mutant group of Pseudomonas aeruginosa PA01 phage phi KZ].

A group of ts mutants of phi KZ phage specific for Pseudomonas aeruginosa was isolated and studied. A phi KZ phage particle has a unique feature: a specific structure as an internal body concerned with DNA packaging which is present in the phage capsid. Ts mutants were distributed into complementation groups. The time of the development block when grown at elevated temperatures was determined for mutants from several groups, the exact stage of the block having been defined for some late ts mutants. As was found for ts759, the stage of connection of heads containing DNA and the inner body with tails was blocked. The results obtained with ts759 allowed to prove the circular location of fibrous material (DNA?) around the inner body. The conditions for phage crosses were revealed. The genetic map of phi KZ is circular. It may be concluded, considering the linear phi KZ DNA structure in capsids, that circular permutations of phage DNA take place during phage maturation or DNA packaging.