SUMMARY Twenty-two different phage-types of were investigated for lysogeny by growing strains singly, in mixtures and by ultraviolet induction. Five of the strains were lysogenic for other members of the group. The phages differed from one another in host-ranges. Eighteen different lytic phages were isolated from sewage with action on one or more of the strains. The host-range of all 23 phages was tested against a number of , Providence and other intestinal organisms. Twelve of the phages had productive cycles of infection on 24 strains of ; 21 of the phages attacked 19 Providence strains. Two of the phages lysed the same 2 out of 40 strains of The efficiencies of plating varied from 10 to unity. No action was demonstrated on any of the or other strains tested. The host-range of 23 phages previously isolated from sewage and from lysogenic was tested against and Providence strains. Three Providence and 2 strains proved susceptible to productive infection by a number of the phages; 15 strains were lysed by one or more of 18 phages. Some of the phages also caused abortive infection associated with cell death in some organisms. The results indicate close ties between the and groups, and between and the Providence strains.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error