Table 1.
Ent | MGE | DGE | lin-Ent | lin-MGE | UDP-Glce | ||
---|---|---|---|---|---|---|---|
MceC | kcat (min−1) | 2.7 ± 0.3 | 1.22 ± 0.05 | n.d.b | 0.61 ± 0.06c | n.d. | 1.19 ± 0.03 |
Km(μM) | 0.94 ± 0.38 | 18.5 ± 2.4 | n.d.b | 17.8 ± 4.6c | n.d. | 87 ± 6 | |
kcat/Km (min−1μM−1) | 2.9 | 0.07 | n.d. | 0.03 | n.d. | 0.014 | |
IroB | kcat (min−1) | 1.8 ± 0.1 | 5.1 ± 0.2 | 3.0 ± 0.1 | 0.57± 0.002 | 0.44 ± 0.03d | n.d. |
Km(μM) | 2.0 ± 0.3 | 48 ± 6 | 72 ± 5 | 36 ±4 | 111 ± 15d | n.d. | |
kcat/Km (min−1μM−1) | 0.9 | 0.11 | 0.04 | 0.02 | 0.004 | n.d. |
Experiments were conducted at room temperature in buffer D (75 mM Tris-HCl pH 8, 5 mM MgCl2 and 2.5 mM TCEP) and in the presence of 500 μM UDP-Glc.
n.d. = not determined.
Substrate inhibition was observed at [lin-Ent] > 64 μM.
Substrate inhibition was observed at [lin-MGE] > 256 μM.
The UDP-Glc concentration was varied in the presence of 100 μM Ent.