Abstract
Cells of S. anatum (ε15), which survived infection with phage ε34, showed resistance (“early immunity” or “paraiaimmunity”) to superinfection with a vilufent mutant ε34 vir at 15 to 30 minutes after ε34 infection, but recovered the sensitivity at 60 minutes. At 90 to 120 minutes, most cells became again resistant to ε34 vir. At this stage, progeny cells, which do not carry ε34, were also resistant to ε34 vir infection but later they lost new character as phenotype and gained properties, including sensitivity to ε34, corresponding to their genotype. From 150 minutes on, cells carrying ε34 and those notcarrying ε34 showed respective phenotype corresponding to respective genotype.
The cells at 15 to 30 minutes adsorbed superinfecting phage, which proved to inject its genetic material into the cells, while the cells at 90 to 120 minutes did not adsorb ε34 vir, due to the change in surface structure of the cells, which was introduced by infection with temperate ε34.
