TABLE 1.
Bacterial strains and plasmids used in this work
| Strain or plasmid | Relevant characteristicsa | Source or reference |
|---|---|---|
| E. coli DH5α | Cloning host | Life Technologies Inc. |
| S. thermophilus strains | ||
| LY03 | Commercial yoghurt strain | IMDST01b |
| TMB 6003 | LY03 with pFL52, Specr | This study |
| TMB 6004 | LY03 with pFL46 | This study |
| TMB 6010 | Gal+ LY03 | This study |
| TMB 6011 | TMB 6010 with pFL52 | This study |
| TMB 6012 | TMB 6010 with integrated pFL41, Emr | This study |
| Plasmids | ||
| pUC19 | Cloning vector, AmprlacZ" | 26 |
| pFL41 | pG+host9 with internal pgmA fragment | 20 |
| pFL42 | pLZ12spec with pgmA with native promoter | 20 |
| pFL46 | pFL42 with galU after pgmA | This study |
| pFL52 | pFL42 with galU replacing pgmA | This study |
a
Emr, erythromycin resistant; Specr, spectinomycin resistant; Ampr, ampicillin resistant.
b
IMDST01, culture collection at Vrije University, Brussels, Belgium.