TABLE 3.
Ability of various E. coli strains to accumulate polyP in response to stresses
| Stress | Accumulation in strainsa
|
|
|---|---|---|
| High | None | |
| Limited nutrient medium | ||
| SM limited for N source | WT | RpoS− |
| RelA− | NtrC− | |
| RpoN− | Utase/UR− | |
| PhoB− | ||
| SM limited for C source | WT | |
| MOPS, 0.1 mM Pi, 2 μg of amino acids/ml | WT | |
| Nutrient downshifts | ||
| LB to MOPS (2 mM Pi, no glucose, no amino acids) | WT | |
| LB to MOPS (0.1 mM Pi, 0.4% glucose, 20 μg of amino acids/ml) | WT | RelA− |
| SM, complete to SM, no N, no amino acids | WT | |
| RpoS− | ||
| RpoN− | ||
| Osmotic (LB, 1.17M NaCl) | WT | RpoS− |
| RelA− | PhoB− | |
| RpoN− | ||
| Acid/alkaline | ||
| LB, pH 4.5 | WT | |
| LB, pH 9.0 | WT | |
| Temperature (LB, 42°C) | WT | |
| Oxidative (LB, 0.1 mM H2O2) | WT | |
a
High represents polyP accumulation of 20 to 500 nmol/mg of protein. None represents polyP levels below 0.1 nmol/mg of protein. No polyP accumulated in ppk ppx cells under any condition. WT, wild type.