Table 4.
Yield of trehalose and percentage of trehalose excreted in strains NZ9000(pNZtpo) and NZ9000(pNZotsBA)a
| Culture type | Mean % trehalose yield ± SD |
Mean % trehalose excreted ± SD |
||
|---|---|---|---|---|
| NZ9000(pNZtpo) | NZ9000(pNZotsBA) | NZ9000(pNZtpo) | NZ9000(pNZotsBA) | |
| Resting cells at pH 6.5 | 14.9b | 10.7b | 26.8b | 21.6b |
| Growing cells | ||||
| pH controlled at 6.5 | 6.5 ± 2.0 (Exp), 11.4 ± 4.0 (Stat) | 5.4 (Exp), 5.2 (Stat)c | 78.0 ± 3.9 (Exp), 86.9 ± 0.6 (Stat) | 80.5 ± 1.3 (Exp), 84.2 ± 0.3 (Stat) |
| Without pH control | 15.8 ± 1.4 (Exp) | 8.5 ± 0.2 (Exp) | 66.7 ± 8.0 (Exp) | 80.7 ± 1.2 (Exp) |
a
The trehalose produced and glucose consumed were quantified by NMR (see Materials and Methods). In growing cells, levels of intracellular and extracellular trehalose were determined for cell extracts and supernatants derived from cultures harvested during mid-exponential (Exp) and stationary (Stat) phases of growth, respectively. Unless stated otherwise, the values are averages of data from at least two independent experiments.
b
Values refer to the experiment shown in Fig. 4.
c
A single experiment was performed.