Table 1 Strains and plasmids used in this study
Strain or plasmid | Genotype or characteristics | Reference or source |
|---|---|---|
Strains | ||
 Lactic acid bacteria strains | ||
  S. thermophilus | Wild type | Our lab |
  L. lactis NZ9000 | L. lactis MG1363 pepN::nisRK; commonly used host for NICE system | [48] |
  L. casei SDMCC050427 | Wild type isolated from Chinese artisanal yogurt | Our lab |
  L. plantarum LA | Wild type isolated from Chinese artisanal yogurt | Our lab |
  L. brevis ATCC 367 | Wild type | [49] |
  L. bulgaricus JB | Wild type isolated from Chinese commercial yogurt | Our lab |
  Leuconostoc lactis SDMCC050430 | Wild type isolated from Chinese artisanal yogurt | Our lab |
  W.cibaria SDMCC050356 | Wild type isolated animal feed additive | Our lab |
 E. coli strains | ||
  DH5α | supE44 ΔlacU169 Φ80lacZΔM15 hsdR17 recA1 endA1 gyrA96 thi-1 relA1 | Novagen |
  BL21 (DE3) | F−ompT hsdSB (rB− mB−) gal dcm | Novagen |
 Plasmids | ||
  pD2gfp | pSec:leiss:Nuc derivative, expresses gfp under PD2 control, CmR | [50] |
  pET28a (+) | Kanr; E. coli expression vector | Novagen |
  pET28a (+)-gfp | Kanr; pET28a (+) carrying NdeI/HindIII-digested product expressing His6-tagged GFP | This study |
  pET28a (+)-gfp-enoM | Kanr; pET28a (+) carrying NdeI/HindIII-digested product expressing His6-tagged GFP-EnoM | This study |
  pET28a (+)-gal | Kanr; pET28a (+) carrying NcoI/XhoI-digested product expressing His6-tagged engineered β-Gal from S. thermophilus SDMCC050237 | Unpublished data |
  pETDuet1 | Apr; E. coli expression vector | This study |
  pETDuet1-gal-enoM | Apr; pETDuet1 carrying BamHI/SalI-digested product expressing His6-tagged β-Gal-enoM | This study |