TABLE 2.
Plasmids used in this study
| Plasmid designation | Relevant characteristics | Source or reference |
|---|---|---|
| Plasmids used for inactivation of rrnB | ||
| pSTL102 | pBR322 carrying a mutant (Spcr Eryr) rrnB operon and its flanking regions in the tet gene | 33 |
| pMA100 | pSTL102 carrying the SalI-SalI deletion in rrnB | This work |
| pMA101 | pMA100 carrying the sacB-Kmr cassette in the BamHI site | This work |
| Plasmids used for inactivation of rrnH | ||
| pLC7-21 | A ColE1 plasmid carrying the rrnH operon and its flanking regions | 6 |
| pC5 | pBR322 carrying rrnH+ (EcoRV fragment of pLC7-21) in the EcoRV site | This work |
| pMA102 | pC5 carrying the SacII-SacII deletion in rrnH | This work |
| pMA103 | pMA102 carrying the sacB-Kmr cassette in the SalI site | This work |
| Plasmids used for inactivation of rrnG | ||
| pLC23-30 | A ColE1 plasmid carrying the rrnG operon and its flanking regions | 6 |
| pC14 | pBR322 carrying rrnG+ (BamHI fragment of pLC23-30) | 7 |
| pNY2 | The SmaI-HpaI region of rrnG in pC14 was replaced with a lacZ+ fragment | This worka |
| pNY30 | pNY2 carrying the sacB-Kmr cassette in the HindIII site | This worka |
| Plasmids used for inactivation of rrnA | ||
| pLC19-3 | A ColE1 plasmid carrying the rrnA operon and its flanking regions | 6 |
| pC1 | pBR322 carrying rrnA+ (BamHI fragment of pLC19-3) in the BamHI site | This work |
| pC1ΔSacII | pC1 carrying the SacII-SacII deletion in rrnA | This work |
| pNY34 | pC1ΔSacII carrying the sacB-Kmr cassette in the EcoRV site | This work |
| Other plasmids | ||
| pBEU49 | A runaway-replication mutant plasmid carrying the recAo281 gene (Apr Kmr) | 35 |
| pBIP3 | A source of the sacB-Kmr cassette (4.7-kb BamHI fragment) | 31 |
| pC4 | pBR322 carrying rrnC+ (EcoRV fragment of pLC22-36) in the EcoRV site | This work |
| pC8 | pBR322 carrying rrnD+ (AflII-PstI fragment of pLC16-6) in the EcoRV site | This work |
a
All cloning experiments for these plasmids were carried out at 30°C with M9-glycerol medium.