TABLE 1.
Bacterial strains, plasmids, and phage used for this study
| Strain or plasmid | Relevant propertiesa | Source or reference |
|---|---|---|
| Escherichia coli strains | ||
| DH5α | General cloning host | BRL |
| ET12567(pUZ8002) | Strain for intergeneric conjugation; Kmr Cmr | 23 |
| Streptomyces noursei strains | ||
| ATCC 11455 | Wild type, nystatin producer | ATCC |
| NDA59 | Mutant with in-frame nysA deletion, nystatin nonproducer | 8 |
| NLD101 | NDA59 with in-frame deletion of the nysL gene | This work |
| Phage | ||
| N95 | Recombinant λ phage containing the nysL gene and flanking regions | 7 |
| Plasmids | ||
| pGEM3Zf(−) | ColE1 replicon; Apr; 3.2 kb | Promega |
| pQE2 | N-terminal six-His tag expression vector | QIAGEN |
| pQNL2 | Vector for heterologous expression of the six-His-NysL protein | This work |
| pSOK20 | pSG5 and ColE1 replicons; oriT; Amr; E. coli-Streptomyces conjugative vector | 29 |
| pSOK804 | E. coli-Streptomyces conjugative and integrative vector; VWBint; ColE1 replicon; oriT; Amr | 24 |
| pNLD1 | nysL replacement vector | This work |
a
Abbreviations: Am, apramycin; Ap, ampicillin; Km, kanamycin; Tc, tetracycline; Cm, chloramphenicol.