TABLE 1.
Bacterial strains and plasmids used in this study
| Strain or plasmid | Relevant feature(s) | Reference or source |
|---|---|---|
| Strains | ||
| Escherichia coli | ||
| EC101 | Cloning host; repA+ kmr | 92 |
| EC101-pNZ-M.Bbrll+Bbr1 | EC101 harboring a pNZ8048 derivative containing the methyltransferase-encoding genes bbrIIM and bbrIIIM from B. breve UCC2003 | 57 |
| XL1-Blue | supE44 hsdR17 recA1 gyrA96 thi relA1 lac F′ [proAB+ lacIq lacZΔM15 Tn10(Tetr)] | Stratagene |
| XL1-Blue-pBC1.2-atsProm | XL1-Blue harboring pBC1.2-atsProm | This study |
| L. lactis | ||
| NZ9000 | MG1363 pepN::nisRK; nisin-inducible overexpression host | 65 |
| NZ9000-pNZ8048 | NZ9000 containing pNZ8048 | This study |
| NZ9000-pNZ-atsR2 | NZ9000 containing pNZ-atsR2 | This study |
| NZ97000 | Nisin A-producing strain | 65 |
| B. breve | ||
| UCC2003 | Isolate from a nursling stool sample | 58 |
| UCC2003-atsR2 | pORI19-tetW-atsR2 insertion mutant of B. breve UCC2003 | This study |
| UCC2003-atsT | pORI19-tetW-atsT insertion mutant of B. breve UCC2003 | This study |
| UCC2003-atsA2 | pORI19-tetW-atsA2 insertion mutant of B. breve UCC2003 | This study |
| UCC2003-atsR2-pBC1.2-atsProm | pORI19-tetW-atsR2 insertion mutant of UCC2003 containing pBC1.2-atsProm | This study |
| Plasmids | ||
| pAM5 | pBC1-pUC19-Tcr | 64 |
| pNZ8048 | Cmr; nisin-inducible translational fusion vector | 65 |
| pNZ-atsR2 | Cmr; pNZ8048 derivative containing a translational fusion of an atsR2-containing DNA fragment to a nisin-inducible promoter | This study |
| pORI19 | Emr repA-negative ori+; cloning vector | 92 |
| pORI19-tetW-atsR2 | Internal 408-bp fragment of atsR2 and tetW cloned into pORI19 | This study |
| pORI19-tetW-atsT | Internal 416-bp fragment of atsT and tetW cloned into pORI19 | This study |
| pORI19-tetW-atsA2 | Internal 402-bp fragment of atsA2 and tetW cloned into pORI19 | This study |
| pBC1.2 | pBC1-pSC101-Cmr | 64 |
| pBC1.2-atsProm | AtsR2 promoter region cloned into pBC1.2 | This study |