TABLE 2.
Effects of carbon sources on expression of E. coli enzyme genes in acclimated Z. palmae/pMFY31-Pgap-xylA/xylB-Pgap-tal/tktA
| Plasmid | Carbon source | Activiya of:
|
|||
|---|---|---|---|---|---|
| XIb (mU/mg) | XKc (U/mg) | TAd (U/mg) | TKe (U/mg) | ||
| pMFY31 | Glucose | <0.01 | <0.01 | 0.01 | 0.02 |
| pMFY31-Pgap-xylA/xylB-Pgap-tal/tktA | Glucose | 45.5 | 2.65 | 0.85 | 0.47 |
| pMFY31-Pgap-xylA/xylB-Pgap-tal/tktA | Xylose | 65.3 | 3.75 | 1.94 | 1.14 |
a
Cells were cultured in T medium containing 40 g/liter glucose or xylose and 100 μg/ml of ampicillin for 48 h at 30°C, and harvested cells were disrupted with an ultrasonic oscillator. The resulting supernatant was used as cell extract.
b
One unit of XI produces 1 μmol of xylulose/min.
c
One unit of XK produces 1 μmol of NADH/min.
d
One unit of TA decreases 1 μmol of NADH/min.
e
One unit of TK decreases 1 μmol of NADH/min.