TABLE 1.
Bacterial strains and plasmids used in this study
| Strain/plasmid | Relevant characteristics | Reference or source |
|---|---|---|
| E. coli | ||
| EC101 | Cloning host; repA+ kmr | 44 |
| EC101-pNZ-M.Bbrll+Bbr111 | EC101 harboring a pNZ8048 derivative containing BbrllM and BbrlllM proteins | 40 |
| XL1-Blue | recA1 endA1 gyrA96 thi-1 hsdR17 supE44 relA1 lac [F′ proAB lacIqZΔM15 Tn10 (Tetr)] | Stratagene |
| L. lactis | ||
| NZ9000 | MG1363, nisin-inducible overexpression host; pepN::nisRK | 62 |
| NZ9700 | Nisin-producing strain | 62 |
| B. breve | ||
| UCC2003 | Isolate from nursling stool | 19 |
| UCC2003-melR1 | pORI19-tet-mel1 insertion mutant of UCC2003 | This study |
| UCC2003-melR2 | pORI19-tet-melR2 insertion mutant of UCC2003 | This study |
| UCC2003-rafR | pORI19-tet-rafR insertion mutant of UCC2003 | This study |
| Plasmids | ||
| pORI19 | Emr ΔrepA ori+; cloning vector | 44 |
| pORI19-tet-melR1 | Internal 421-bp fragment of melR1 and tetW cloned in pORI19 | This study |
| pORI19-tet-melR2 | Internal 456-bp fragment of melR2 and tetW cloned in pORI19 | This study |
| pORI19-tet-rafR | Internal 331-bp fragment of rafR and tetW cloned in pORI19 | This study |
| pAM5 | pBC1-puC19-Tcr | 45 |
| pNZ8048 | Cmr; nisin-inducible translational-fusion vector | 62 |
| pNZ8150 | Cmr; nisin-inducible translational-fusion vector | 42 |
| PQE30 | Ampr; IPTG-inducible vector | Qiagen |
| pNZ-MelR1-His | melR1 with His tag cloned downstream of nisin-inducible promoter on pNZ8048 | This study |
| pnz-MelR2-His | melR2 with His tag cloned downstream of nisin-inducible promoter on pNZ8150 | This study |
| pQE30-RafR | rafR cloned into the IPTG-inducible vector PQE30 | This study |