[Phage T4 partial diploidy obtained with the method of DNA interrupted injection. I. Analysis of the genetic structure and phage progeny reproduction process].

Phage T4 chromosome fragmentation is shown to take place when DNA injection is interrupted, a fragment length being strictly controlled by the interval from the moment of adsorbtion till the moment of an interruption. Populations of the bacteria cells infected by the phage T4 partial diploids are produced with the method of DNA interrupted injection. In the population a merodiploid involves some phage T4 amber mutant and a phage "wild" type chromosome fragment of the size controlled. To construct merodiploids the amber mutant in gene 43 and the mutant in gene 32 with the higher and the lower recombination frequency, accordingly, are used. Every merodiploid which is the heterozygote by one of these genes or which is the heterozygote by the late genes is determined to reproduce mixed phage progeny. Both the mean of the burst and the parent genotypes ratio in progeny either in the E. coli CR-63 cells or in the E. coli B depend on neither the heterozygote genetic structure nor the diploid region size. The results obtained conclude that phage genes express their function in the small fragments and the fragment recombination with the mutant partner whole chromosome follows their autonomous replication.