TABLE 1.
Bacterial strains and plasmids used in this study
| Strain or plasmid | Relevant characteristics | Reference or source |
|---|---|---|
| Strains | ||
| E. coli EC101 | Cloning host; repA+ Kanr | 30 |
| L. lactis strains | ||
| NZ9000 | MG1363, nisin-inducible overexpression host; pepN::nisRK | 14 |
| NZ9000-pNZ-αamy | NZ9000 containing pNZ-αamy | This study |
| NZ9000-pNZ-pull | NZ9000 containing pNZ-pull | This study |
| B. breve strains | ||
| UCC2003 | Isolate from nursling stool | 37 |
| UCC2003-apuB | pORI19-apuB insertion mutant of UCC2003 | This study |
| Plasmids | ||
| pNZ8048 | Cmr; nisin-inducible translational fusion vector | 14 |
| pNZ-αamy | Cmr; pNZ8048 derivative containing translational fusion of α-amylase encoding DNA fragment to nisin-inducible promoter | This study |
| pNZ-pull | Cmr; pNZ8048 derivative containing translational fusion of pullulanase encoding DNA fragment to nisin-inducible promoter on pNZ8048 | This study |
| pTGB019 | Cmr; 6.5-kb derivative of pVE6007 harboring temperature-sensitive repA gene | L. Steidler and S. Neirinck, unpublished results |
| pORI19 | Emr RepA− Ori+; cloning vector | 30 |
| pORI19-apuB | Internal 1-kb fragment of apuB cloned in pORI19 | This study |