TABLE 1.
Strains and plasmids used in this study
| Strain or plasmid | Relevant characteristics | Source or reference |
|---|---|---|
| Strains | ||
| L. lactis | ||
| NZ9000 | MG1363 pepN::nisRK; wild-type strain | 24 |
| NZ9000ΔribA | NZ9000 derivative with a 783-bp deletion in ribA | This study |
| CB010 to CB021 | NZ9000 derivatives that have increased resistance to roseoflavin | This study |
| E. coli | ||
| BSV11 | Mutation in 3,4-dihydroxy-2-butanone 4-phosphate synthase | 5 |
| BSV13 | Mutation in riboflavin synthase α chain | 5 |
| BSV18 | Mutation in GTP cyclohydrolase II | 5 |
| EC1000 | Kmr; MC1000 derivative, carrying a single copy of pWV01 repA in glgB | 28 |
| TOP10 | Commercial cloning host used for pCR2.1-TOPO | Invitrogen, Groningen, The Netherlands |
| Plasmids | ||
| pNZ8048 | Cmr; inducible expression vector carrying the nisA promoter | 10 |
| pORI280 | Emr; LacZ+, ori+ of pWV01; replicates only in strains providing repA in trans | 28 |
| pCR2.1-TOPO | Kmr Ampr; commercial cloning vector | Invitrogen, Groningen, The Netherlands |
| pORI280ΔribA | pORI280 derivative containing a truncated version of ribA and the surrounding regions | This study |
| pPTPL | Promoter probe vector | This study |
| pCB001 | pCR2.1-TOPO with NZ9000 ribA inserted | This study |
| pCB002 | pCR2.1-TOPO with NZ9000 ribA 5′ section inserted | This study |
| pCB003 | pCR2.1-TOPO with NZ9000 ribA 3′ section inserted | This study |
| pCB004 | pCR2.1-TOPO with a truncated NZ9000 ribA inserted | This study |
| pCB005 | pCR2.1-TOPO with NZ9000 ribB inserted | This study |
| pNZdhbp | pNZ8048 containing NZ9000 ribA 5′ section under the control of the nisA promoter | This study |
| pNZgchII | pNZ8048 containing NZ9000 ribA 3′ section under the control of the nisA promoter | This study |
| pNZA | pNZ8048 containing NZ9000 ribA under the control of the nisA promoter | This study |
| pNZB | pNZ8048 containing NZ9000 ribB under the control of the nisA promoter | This study |
| pNZBA | pNZ8048 containing NZ9000 ribA and ribB under the control of the nisA promoter | This study |
| pNZBAH | pNZ8048 containing NZ9000 ribA, ribB, and ribH under the control of the nisA promoter | This study |
| pNZGBA | pNZ8048 containing NZ9000 ribG, ribB, and ribA under the control of the nisA promoter | This study |
| pNZGBAH | pNZ8048 containing NZ9000 ribG, ribB, ribA, and ribH under the control of the nisA promoter | This study |
| pPTPLop | pPTPL containing the promoter region upstream of the NZ9000 rib operon | This study |
| pPTPLcbop | pPTPL containing the promoter region upstream of the CB010 rib operon | This study |
| pPTPL-P2 | pPTPL containing the promoter region within ribB of NZ9000 | This study |