TABLE 1.
Expression and coexpression of E and SNUC
| Plasmid(s) | Time of IPTG additiona (min) | Time of Mg/Ca additiona (min) | Ghost formationb | Maximum inactivationc | Δt[maximum inactivation]d (h) |
|---|---|---|---|---|---|
| pAW12, pHSSNUC | — | — | + | 4 | 2.5-4 |
| — | Inoculation | Impaired | 4-5 | 3.5-4 | |
| — | 0 | Impaired | 4-5 | 3.5 | |
| — | +60 | + | 4-6 | 2.5-4 | |
| pAW12 | — | — | + | 4 | 1.3-1.5 |
| pHSSNUC | — | +60 | ND | 1-2 | 4 |
| pML1, pSNUC1 | — | — | + | 3-4 | 5-6 |
| — | +90 | + | 2-3 | 6 | |
| −45 | — | + | 2-3 | 5 | |
| 0 | 0 | Impaired | ≥7-8* | >8 | |
| 0 | +90 | + | ≥7-8* | >8 | |
| −45 | +90 | + | ≥7-8* | 6->8 | |
| +90 | +90 | + | ≥7-8* | >8 | |
| pML1 | −45 | +90 | + | 2-4 | 5-7 |
| — | — | + | 2-4 | 5-7.5 | |
| pSNUC1 | −45 | +90 | ND | 2-3 | 2-2.5 |
a
Times refer to the time of temperature upshift (0 min). —, no addition; inoculation, Mg and Ca added at the time of culture inoculation.
b
+, >95% of bacterial particles were ghosts at the completion of lysis; impaired, protein E-mediated lysis impaired, giving elevated numbers of nonlysed cells; ND, no ghosts detected.
c
Maximum in activation in log units [log(CFUmax) − log(CFUmin]. *, viable cells below detection limit.
d
Time period from the temperature upshift to 42°C to the timepoint of minimum variability.