[Transmission of amber mutants of bacteriophage T4. III. Thermostability of the replication of amber mutants in cells of a non-permissive host is typical for the majority of phage tail genes].

The article deals with determination of the spreading of the earlier discovered phenomenon of the temperature sensitivity of multiplication of T4 phage amber mutants. On the basis of the study of the dependence of multiplication of 50 amber mutants in 22 genes of T4 phage tail in the cells of non-permissive host on the incubation temperature in the range of 15-41 degrees C, the following conclusion is drawn: temperature sensitivity of multiplication of amber mutants appears to be gene-specific and is widely spread among T4 phage genes, i.e. in the case of amber mutants the burst size decreases, even for 14 tail genes, by several orders with the increase in incubation temperature. Temperature sensitivity of multiplication is typical of amber mutants in the genes whose proteins are either of small number in a phage particle (several molecules) or play the role of catalytic factors. Moreover, genes, amber mutants of which possess temperature sensitivity of multiplication, map in defined clusters.