TABLE 3.
Effect of the Gal enzymes on growth and product yields in MST medium
| Strain | PGM activity (U mg of protein−1) | GalK activity (U mg of protein−1) | GalT activity (U mg of protein−1) | μmax (h−1)a | Ylactose, galactose (mol of carbon mol of carbon−1)b | Ylactose, EPS (g mol of carbon−1)c |
|---|---|---|---|---|---|---|
| LY03 | 0.87 ± 0.03d | 0.05 ± 0.02 | 1.3 ± 0.1 | 1.4 ± 0.2 | 0.39 ± 0.03 | 0.17 ± 0.04 |
| TMB 6010 | 0.98 ± 0.03 | 0.67 ± 0.04 | 17.3 ± 2.1 | 1.2 ± 0.0 | 0.18 ± 0.05 | 0.24 ± 0.02 |
| TMB 6011 | 0.79 ± 0.20 | 1.14 ± 0.07 | 16.4 ± 1.3 | 1.1 ± 0.1 | 0.12 ± 0.03 | 0.27 ± 0.02 |
| TMB 6012 | 0.01 ± 0.00 | 0.46 ± 0.11 | 12.9 ± 3.4 | 1.1 ± 0.1 | 0.27 ± 0.06 | 0.36 ± 0.02 |
a
μmax, maximum specific growth rate.
b
Ylactose, galactose, yield of galactose when organisms are grown on lactose.
c
Ylactose, EPS, yield of EPS when organisms are grown on lactose.
d
Average ± standard deviation based on the results obtained with at least two independent cultures.