TABLE 1.
Strains and plasmids used in this studya
| Strain or plasmid | Genotype or properties | Source or reference |
|---|---|---|
| L. casei | ||
| BL23 | Wild type | CECT 5275 |
| BL282 | BL23 gutB (480-bp deletion in gutB) | This work |
| BL285 | BL23 gutR (frameshift at PstI restriction site) | This work |
| BL286 | BL23 gutM (frameshift at PstI restriction site) | This work |
| BL291 | BL286 containing pT1NgutM; Ermr | This work |
| BL307 | BL285 containing pT1NgutR; Ermr | This work |
| ATCC 334 | Wild type; carries an insertion element in gutR | ATCC |
| L. lactis MG1363 | Plasmid- and phage-free derivative of NCDO712 | 9 |
| E. coli | ||
| DH5a | F−endA1 hsdR17 gyrA96 thi-1 recA1 relA1 supE44 DlacU169 (F80 lacZ DM15) | Stratagene |
| M15(pREP4) | Nals, Strs, Rifs, Thi−, Lac−, Ara+, Gal+, Mtl−, F−, RecA+, Uvr+, Lon+ | Qiagen |
| Plasmids | ||
| pRV300 | Suicide vector carrying Ermr from pAMb1 | 15 |
| pRVB1 | pRV300 with a fragment carrying a deletion in gutB | This work |
| pRVR1 | pRV300 with a frameshift at PstI site in gutR | This work |
| pRVM4 | pRV300 with a frameshift at PstI site in gutM | This work |
| pT1NX | Contains the P1 constitutive promoter; Ermr | 23 |
| pT1NgutM | pT1NX containing gutM-encoding region | This work |
| pT1NgutR | pT1NX containing gutR-encoding region | This work |
| pQE30 | Ampr | Qiagen |
| pQEgutR | pQE30 containing gutR-encoding region | This work |
| pQEgutM | pQE30 containing gutM-encoding region | This work |
a
CECT, Colección Española de Cultivos Tipo; ATCC, American Type Culture Collection; Ampr, ampicillin resistant; Ermr, erythromycin resistant; Nals, nalidixic acid sensitive; Strs, streptomycin sensitive; Rifs, rifampin sensitive.