Repression phagique de l'hémolysine delta chezStaphylococcus aureus

Summary

The effects of double, simultaneous, or successive lysogenisation of BSS strain ofS. aureus by two staphylococcal phages, both isolated from the same strain, have been studied. These phages (φRE andφD) are easily distinguished electronmicroscopically by the morphology of the virions as well as by the aspect of the plaques on the BSS. Lysogenization of BSS byφD is always accompanied by repression ofβ-haemolysin (conversion), but lysogenisation byφRE is only rarely accompanied by the loss of (δ-haemolysin (the frequency of the phenomenon suggests a transduction). In double lysogenization of BSS strain byφRE andφD, the sequence of lysogenisation does not, apparently, play an important role.