TABLE 3.
Expression of the PurR-controlled genes glyA and purA as affected by mutations in pbuE of B. subtilis using a glyA-lacZ transcriptional fusion and determination of succinyl-AMP synthase (PurA) activity
| Strain | Relevant genotype | PbuE status | Activity (U/mg of protein)a
|
Pool size (nmol/mg dry weight)b
|
|||||
|---|---|---|---|---|---|---|---|---|---|
| PurA with no purine addedc | β-Galactosidase with:
|
||||||||
| No purine added | Adenine | Guanosine | ATP | GTP | PRPP | ||||
| KN05n | amyE::[pKN05n glyA′-lacZ (neo)] | Wild type | 9 | 427 | 210 | 663 | 2.4 | 1.3 | 0.7 |
| ED509 | amyE::[pKN05n glyA′-lacZ (neo)] pbuE1 | Overexpressed | 22 | 1,409 | 231 | 1,599 | 3.0 | 1.5 | 1.4 |
| ED508 | amyE::[pKN05n glyA′-lacZ (neo)] pbuE::pLJ42 (cat) | Deficient | 7 | 495 | 223 | 668 | 2.8 | 1.3 | 0.7 |
a
β-Galactosidase activity was determined as described in the legend to Table 2. Succinyl-AMP synthase activity was determined as described in reference 2.
b
Pools were determined in cells growing without purine addition (12).
c
Cells were grown in minimal medium, adenine was added at a concentration of 150 μg/ml, and guanosine was added at 300 μg/ml.