| Abstract: | When studying the single cycle of the multiplication of gene 26 mutant amN131 of phage T4, like in temperature shift experiments, the yield of this mutant in non-permissive host depends greatly on the temperature. The burts size of phage in Escherichia coli B is found to be 3.3 phage particles at 25 degrees C, 1.6 at 30 degrees C, 0.051 at 37 degrees C and 0.0007 at 41 degrees C. In the case of permissive host (E. coli CR-63) the burst size per cell decreases from 158 to 49 phage particles at the same temperature interval. The results of the single-burst experiments indicate, that when the incubation temperature increases, the number of E. coli B cells, in which the phage particles maturate, also decreases. It results in the dependence of the transmission coefficient value on the temperature. The transmission coefficient in the conditions favourable for the maturation of the phage is found to be 0.80. It is shown by several methods that the temperature sensitivity of the multiplication of the mutant amN131 in bacterial cells is entirely due to amber mutation in genome of the phage. Therefore the amber mutants having high temperature sensitivity when maturating in non-permissive host cells exist among ordinary amber mutants of phage T4. |
