Bacteria as “Carriers” of Bacteriophage.

Abstract

There has been a great deal of discussion in the literature regarding the production of bacteriophage from bacterial cultures. A classical example of this phenomenon is the B. coli of Lisbonne and Carrére 1 which is able to elaborate lytic principle for B. dysentery Shiga. This subject has been treated extensively by one of us (McKinley 2 ) in another publication. More recently Muckenfuss 3 has studied these cultures supplied to him by us and he concludes that such organisms as B. coli Lisbonne may be made lysogenic by exposing the organisms to a bacteriophage and that the organisms so exposed then “carry” the lytic principle and antibodies are produced against the bacteriophage when the “phage infected” bacteria are used for immunization. However, this author states that failure of such antibodies to appear on immunization with bacteria does not necessarily indicate that bacteriophage is not present.

We have attempted to “contaminate” or “infect” a strain of B. coli with a bacteriophage lytic for Staphylococcus aureus. The organism and lytic principle employed are at wide enough variance to preclude the possibility of any intimate relation existing between them. The lytic principle was active in 1:10,000,000,000 dilution against its sensitive strain of staphylococcus. B. coli was sown in bouillon and after 12 hours'incubation 1 cc. of the bacteriophage was added to the culture. Incubation was then prolonged to 24 hours. There was no evidence whatever of lysis, as might be expected. After 24 hours'incubation dilution plates were made from the B. Coli-Staphylococcus bacteriophage broth culture in order to obtain isolated colonies of the B. Coli. Typical colonies were picked and sown in broth and incubated over night. This culture was then heated at 58.5°C. for 30 minutes to destroy the microbes and 2 cc. of this heated culture were added to a tube of broth along with an inoculum of the sensitive Staphylococcus aureus.