TABLE 2.
Phage A500 and A511 adsorption deficiency of gtcA mutant
| Strain | % Efficiency of phage adsorptiona
|
|
|---|---|---|
| A511 | A500 | |
| 4b1 | 100 | 100 |
| M44 | 26.2 | 7.0 |
| M44::pPL2 | 18.7 | 9.1 |
| M44::pPL95 | 72.9 | 57.4 |
Adsorption of phages was calculated by determining the number of PFU remaining in the supernatant following 30 min of incubation of the phage-bacterium mixture at 37°C and subtracting it from the total PFU/ml of A511 (ca. 1.41 × 105 PFU/ml) or A500 (ca. 1.4 × 104 PFU/ml) added to the bacteria (ca. 1 × 108 CFU/ml). Adsorption efficiency was indicated relative to adsorption on the parental strain 4b1 (set as 100%). The serotype 4b strain F2365 (11) was used as an indicator for the enumeration of total PFU/ml in the inoculum and in the supernatant, and infections were done as described previously (14). The phage adsorption assay for each tested phage was done at least twice. The results shown are from a representative experiment.