Table 2.
Promoter activity determined by LacZ reporter fusion analysis
| LacZ fusion | Plasmid copy number (WT/Δzur) | Normalized Miller Units | Fold change (Δzur/WT) |
|---|---|---|---|
| WT-znuC | 5.45 ± 0.73 | 6343.95 ± 237.68 | 2.60 |
| Δzur-znuC | 16507.10 ± 344.19 | ||
| WT-znuA | 11.52 ± 0.92 | 12281.64 ± 428.30 | 7.77 |
| Δzur-znuA | 95498.09 ± 1962.30 | ||
| WT-ykgM | 3.09 ± 0.88 | 118.64 ± 6.77 | 4.71 |
| Δzur-ykgM | 559.29 ± 28.14 | ||
Notes: The promoter DNA regions upstream znuC, znuA and ykgM were cloned into the pRS551 plasmid, respectively, to fuse with the promoterless lacZ gene. β-Galactosidase activity (miller units) was detected to represent the promoter activity. Copy number of recombinant pRS551 was determined by real-time quantitative PCR, with the primers specific for the borne lacA gene. The detecting fold change of plasmid copy number was set to be 1 to generate a normalization factor that was subsequently used for generating the normalized fold change of promoter activity (miller units) in WT in relative to Δzur.