TABLE 3.
Activities of enzymes involved in initial sugar metabolism of glucose and fructose and biosynthesis of sugar nucleotides in glucose- and fructose-grown cultures of Lactococcus lactis NZ4010 and MG1614
| Enzyme | Mean activity (nmol mg of protein−1 min−1 ± SD (n = ≥4) in indicated strain grown on:
|
|||
|---|---|---|---|---|
| Glucose
|
Fructose
|
|||
| NZ4010 | MG1614 | NZ4010 | MG1614 | |
| Mannose PTS | 29 ± 13 | 21 ± 5 | 21 ± 5 | 28 ± 8 |
| Phosphoglucose isomerasea | 4,318 ± 349 | 4,085 ± 357 | 3,415 ± 289 | 3,148 ± 544 |
| 6-Phosphofructokinase | 173 ± 44 | 189 ± 105 | 205 ± 37 | 210 ± 44 |
| α-Phosphoglucomutasea | 345 ± 41 | 295 ± 37 | 295 ± 7 | 290 ± 40 |
| UDP-glucose pyrophosphorylasea | 5.5 ± 2.2 | 4.2 ± 1.3 | 5.3 ± 1.9 | 4.4 ± 0.8 |
| UDP-galactose-4-epimerasea | 182 ± 36 | 143 ± 35 | 182 ± 7 | 190 ± 18 |
| TDP-glucose pyrophosphorylasea | 34 ± 9 | 29 ± 2 | 27 ± 6 | 22 ± 9 |
| TDP-rhamnose biosynthetic system | 16 ± 3 | 14 ± 6 | 14 ± 1 | 15 ± 1 |
| Fructose PTS | 29 ± 9 | 30 ± 14 | 22 ± 6 | 23 ± 9 |
| 1-Phosphofructokinase | 248 ± 93 | 246 ± 54 | 658 ± 86 | 628 ± 134 |
| FBPase | 3.1 ± 0.8 | 3.5 ± 0.6 | 1.9 ± 0.2 | 2.2 ± 0.6 |
a
The reversed reaction was used for measuring the activities.