TABLE 1.
Composition and GS yield in different chemically defined mediaa used in this work
| Component or GS yield | Content (g/liter) in: |
|||
|---|---|---|---|---|
| GATb | G4/4c | GATF1 | GATF2 | |
| Glycerol | 10.0 | 10.0 | 10.0 | 10.0 |
| (NH4)2SO4 | 5.0 | 5.0 | 5.0 | |
| l-Arginine | 10.0 | |||
| l-Phenylalanine | 1.0 | 1.0 | 0.25 | |
| l-Methionine | 0.5 | |||
| l-Histidine | 1.3 | |||
| K2HPO4 | 6.5 | 6.5 | 6.5 | 6.5 |
| KH2PO4 | 1.7 | 1.7 | 1.7 | 1.7 |
| Tris-HCl | 6.0 | 6.0 | 6.0 | |
| MgCl2·6H2O | 0.2 | 0.2 | 0.2 | 0.2 |
| CaCl2·2H2O | 0.1 | 0.1 | 0.1 | 0.1 |
| MnCl2·4H2O | 0.01 | 0.01 | 0.01 | 0.01 |
| FeCl3·6H2O | 0.0002 | 0.0002 | 0.0002 | 0.0002 |
| GS yieldd (mg/liter) | 109 ± 24 | 1356 ± 156 | 173 ± 24 | 263 ± 35 |
a
GAT, basal minimal medium; G4/4, medium found to be optimal for GS production; GATF1 and GATF2, phenylalanine-containing GAT media. GATF2 was found to be the optimal minimal medium and the most cost-effective in terms of 13C/15N-GS production.
b
Analogous to 1% G2T6 medium used in reference 22, but reduced here in ammonium sulfate and Tris.
c
Analogous to fructose-containing medium from reference 24.
d
GS average yield ± standard deviation over several (n) independent fermentation experiments (for GAT, n = 6; for G4/4, n = 10; for GATF1, n = 6; for GATF2, n = 4).