Table 1.
Substrate | Sequence | kcat (s−1) | Km (μM) | kcat/Km (μM−1 s−1) |
---|---|---|---|---|
WT2 | 5′-TTAGGGTTAGGGTTA-3′ 3′-AATCCCAATCCCAAT-5′ |
0.485 ± 0.022 | 0.519 ± 0.109 | 0.933 |
WT1 | 5′-TTAGGGTTAGGGTTA-3′ 3′-AATCCCAATCCCAAT-5′ |
0.451 ± 0.025 | 0.523 ± 0.137 | 0.862 |
WT3 | 5′-TTAGGGTTAGGGTTA-3′ 3′-AATCCCAATCCCAAT-5′ |
0.675 ± 0.037 | 0.519 ± 0.134 | 1.302 |
TTT | 5′-TTTGGGTTTGGGTTT-3′ 3′-AAACCCAAACCCAAA-5′ |
0.703 ± 0.052 | 0.412 ± 0.149 | 1.705 |
ATT | 5′-ATTGGGATTGGGATT-3′ 3′-TAACCCTAACCCTAA-5′ |
0.566 ± 0.034 | 0.267 ± 0.089 | 2.116 |
Random | 5′-GTACGAGTCGAGTCA-3′ 3′-CATGCTCAGCTCAGT-5′ |
0.580 ± 0.021 | 0.313 ± 0.059 | 1.854 |
Bold T indicates the position of an hmU modification.
Glucosylation reactions were conducted with hmU DNA substrate concentration of 0, 0.195, 0.391, 0.781, 1.563, 3.125, 6.25, 12.5, and 25 μM and fixed enzyme and UDP-glucose concentrations of 18 μM and 1mM, respectively. UDP cleaved is plotted vs substrate concentration and nonlinear regression was performed to determine kinetic parameters.