Table 4.
Substrate specificities of DrBCAT, eBCAT, and HB8BCAT
| α-Keto acid substratea |
DrBCAT |
eBCAT |
HB8BCAT |
|||
|---|---|---|---|---|---|---|
| Relative activity (%) | Sp act | Relative activity (%) | Sp act | Relative activity (%) | Sp act | |
| KIC | 100.0 | 154.44 | 100.0 | 5.26 | 100.0 | 8.45 |
| KIV | 62.5 | 96.57 | 36.5 | 1.92 | 41.6 | 3.51 |
| KMV | 34.9 | 53.95 | 61.5 | 3.24 | 28.3 | 2.39 |
| KMTB | 22.7 | 34.98 | 26.4 | 1.39 | 14.5 | 1.22 |
| 2-Ketohexanoic acid | 57.1 | 88.20 | 78.4 | 4.12 | 30.7 | 2.60 |
| 2-Oxovaleric acid | 51.0 | 78.84 | 66.9 | 3.52 | 23.5 | 1.99 |
a
l-Glutamate as an amino group donor reacted with α-keto acid. The activity of KIC was set at 100%. Abbreviations used: KIC, α-ketoisocaproate; KMV, α-keto-β-methylvalerate; KIV, α-ketoisovalerate; KMTB, ketomethiobutyrate.