FIG 3.

Lysogenization by Φ1207.3. Tenfold serially diluted phage preparations obtained from mitomycin C-treated FR1 culture were used to lysogenize the novobiocin-resistant and competence-deficient S. pneumoniae FP11. The minimum number of phages required to obtain a detectable lysogenization was 10³, whereas no lysogens could be detected (<2.8 × 10⁻⁸ lysogens per recipient) using lower phage numbers. The lysogenization frequency was calculated as number of lysogens per recipient cell.