TABLE 3.
Substrate specificity of d-hydantoinase (for cyclization reaction) from Blastobacter sp. strain A17p-4a
| Substrate | Km (mM) | Vmax (μmol [min × mg]−1) | Vmax/Km (μmol [min × mg]−1 mM−1) |
|---|---|---|---|
| Half-amide (phthalamidic acid) | 23.0 ± 2.0 | 0.15 ± 0.02 | 0.0065 ± 0.0002 |
| N-Carbamoyl amino acid | |||
| Hydantoic acid | 31.0 ± 0.2 | 0.11 ± 0.01 | 0.0035 ± 0.0005 |
| β-Ureidopropionate | 11.0 ± 0.7 | 0.62 ± 0.04 | 0.056 ± 0.001 |
| N-Carbamoyl-d-alanine | 36.0 ± 1.7 | 4.1 ± 0.3 | 0.11 ± 0.01 |
a
Cyclization reactions and analysis were carried out as described in Materials and Methods with test compounds at 1 to 100 mM as the substrates. The kinetic constant values are averages ± the standard deviation of three different determinations.