TABLE 1.
Verification of selected DNA microarray results by quantitative RT-PCR
| Gene | Ratio of expressiona
|
|||
|---|---|---|---|---|
| Nitrogen
|
NtrC
|
|||
| RT-PCRb | Microarray | RT-PCRb | Microarray | |
| amtB (PP5233) | 62.1 ± 35.9 | 25.4 | −75.8 ± 17.4 | −9.0 |
| glnK (PP5234) | 9.2 ± 3.2 | 5.7 | −4.9 ± 1.2 | −2.6 |
| gdhA (PP0675) | −2.9 ± 0.5 | −3.6 | 3.0 ± 1.1 | 2.5 |
| zwf-1 (PP1022) | −3.8 ± 1.8 | −6.6 | 3.1 ± 1.0 | 5.7 |
| gap-1 (PP1009) | −2.5 ± 0.43 | −2.9 | 3.6 ± 0.6 | 2.6 |
| glpF (PP1076) | −1.4 ± 0.1 | −1.7 | 7.5 ± 0.8 | 4.7 |
| phaC (PP5005) | 4.2 ± 1.3 | 2.3 | 1.2 ± 0.2 | 1.2 |
| GA1 (PP5008) | 4.7 ± 0.8 | 3.4 | 1.1 ± 0.1 | 1.1 |
| glgA (PP4050) | 4.6 ± 1.8 | 2.4 | 1.7 ± 0.5 | 1.7 |
| glgX (PP4055) | 32.2 ± 19.7 | 11 | −3.0 ± 1.3 | −2.4 |
a
Positive values for the ratio of expression in the nitrogen arrays indicated that the gene was upregulated in the presence of serine, and negative values indicated it was upregulated in the presence of ammonium plus serine. Positive values for the NtrC arrays indicated that the gene was upregulated in the mutant strain, and negative values indicated that it was upregulated in the wild-type strain. The same criteria were used for the quantitative RT-PCR data.
b
The quantitative RT-PCR values are the means ± standard deviations of at least three independent experiments.