S. faecalis strain DS 5 has been shown previously to contain three plasmids, pAMα1, pAMβ1, and pAMγ1. Mixed incubation of DS 5 with strain JH 2-2, a plasmid free S. faecalis recipient, results in the transfer of pAMα1 (which determines resistance to tetracycline) and/or pAMλ1. Analyses of recipients carrying various combinations of these plasmids have revealed the pAMγ1 codes for toxin (hemolysin) production and two bacteriocin activities. JH 2-2 strains carrying both pAMα1 and pAMγ1, or pAMγ1 only, can donate their plasmids to other recipients, whereas strains carrying only pAMα1 cannot serve as donor. This indicates that pAMγ1 actually mobilizes the otherwise nontransferable pAMα1.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of bacteriology|
|State||Published - Dec 1 1975|