Table 1.
Bacterial strains, plasmids and phages
| Strain, plasmid or phage | Relevant characteristics | Source or Reference |
|---|---|---|
| Bacteria | ||
| L. lactis subsp. lactis | ||
| M138 | Industrial strain, Lac+ Prt+ Nisr | Mauri Laboratories, Moorebank, Australia |
| LM0230 | Lac− Prt−, plasmid-free derivative of c2 | Efstathiou and McKay, 1977 |
| LM0230Smr | Smr derivative of LM0230 | Duan et al., 1996 |
| LM0230Fusr | Fusr derivative of LM0230 | Duan et al., 1996 |
| E. coli | ||
| NM522 | Transformation host | Gough and Murray, 1983 |
| Plasmids | ||
| pGB301 | 9.8 kb streptococcal vector, Emr, Cmr | Behnke and Gilmore, 1981 |
| pGEM7Zf(+) | 3 kb E.coli vector encoding Ampr and lacZ screening | Promega Corporation, Madison, WI |
| pMU1327 | 7.0 kb streptococcal vector, Emr | Achen et al., 1986 |
| pND852 | Native plasmid of M138,φr Nisr, 56 kb | This study |
| pND817 | 12.3 kb, 2.6 kb HpaII fragment from pND852 cloned into the HpaII site of pGB301 | This study |
| pND821 | 5.6 kb, 2.6 kb HpaII fragment from pND817 cloned into the ClaI site of pGEM-7Zf(+) | This study |
| pND835 | 1225 bp AluI fragment encoding abiI cloned into pMU1327 at the SmaI site | This study |
| pND839 | Frame-shift mutation at the unique EcoRI site of pND817 | This study |
| Phages | ||
| φ712 | Small isometric-headed phage propagated on LM0230 | M.J. Gasson, AFRC Institute of Food Research, Norwich, UK |
| φc2 | Prolate-headed phage propagated on LM0230 | L.L. McKay, University of Minnesota, Minn. |
Amp, ampicillin; Cm, chloramphenicol; Em, erythromycin; Fus, fusidic acid; Nis, nisin; Sm, streptomycin; Lac, lactose utilisation; Prt, proteinase; φr, phage resistance.