TABLE 2.
Bactericidal spectra of carotovoricin Er preparations after incubation with various strains of E. carotovora subsp. carotovoraa
| Preincubation strain | Residual killing activity in units
|
|||
|---|---|---|---|---|
| 645Ar | EC-2 | N786 | P7 | |
| None | 300 | 50 | 60 | 40 |
| Er | 300 | 50 | 60 | 40 |
| N786 | 300 | 50 | 0 | 1 |
| P7 | 300 | 50 | 0 | 1 |
| EC-2 | 1 | 0 | 60 | 40 |
| 645Ar | 0 | 0 | 0 | 0 |
a
A carotovoricin Er preparation (1 μl of 1 mg of protein/ml) was incubated with formaldehyde-fixed bacteria (100 μl) at 30°C for 30 min, followed by centrifugation at 12,000 × g at 0°C for 5 min. The supernatants obtained were assayed for killing activity to various strains as described in Materials and Methods. The experiments were repeated five times, and a representative set of data is shown.