TABLE 2.
Frequency of transfer detected in filter-mating experiments
| Filter-mating expt parameters | No. and type of Tcr isolates | Transfer frequency |
|---|---|---|
| Streptococcus mitis NCTC 12261 | No spontaneous mutants | |
| S. mitis + V. dispar | 1.1 × 103 colonies | 1.6 × 10−6/recipient |
| S. mitis + V. dispar + DNase | 2.9 × 103 transconjugants | 4.1 × 10−6/recipient |
| S. mitis + pAM120 | 29 transformants | 7.8 × 10−2/ng DNA |
| S. mitis + pAM120 + DNase | No transformants | |
| S. oralis NCTC 11427 | No spontaneous mutants | |
| Streptococcus oralis + V. dispar | 3.3 × 103 colonies | 5.6 × 10−5/recipient |
| S. oralis + V. dispar + DNase | 6.7 × 104 transconjugants | 5.7 × 10−5/recipient |
| S. oralis + pAM120 | 3,120 transformants | 8.4/ng DNA |
| S. oralis + pAM120 + DNase | 6 transformants | 1.6 × 10−2/ng DNA |
| Streptococcus parasanguinis NCTC 55898 | No spontaneous mutants | |
| S. parasanguinis + V. dispar | 1.8 × 103 colonies | 4.6 × 10−6/recipient |
| S. parasanguinis + V. dispar + DNase | 8.0 × 103 transconjugants | 5.2 × 10−6/recipient |
| S. parasanguinis + pAM120 | 512 transformants | 1.4/ng DNA |
| S. parasanguinis + pAM120 + DNase | 5 transformants | 1.3 × 10−2/ng DNA |
| S. salivarius NCTC 8618 | No spontaneous mutants | |
| S. salivarius + V. dispar | 2.6 × 103 colonies | 8.7 × 10−5/recipient |
| S. salivarius + V. dispar + DNase | 4.6 × 103 transconjugants | 4.5 × 10−5/recipient |
| S. salivarius + pAM120 | 22 transformants | 5.9 × 10−2/ng DNA |
| S. salivarius + pAM120 + DNase | No transformants |