Table 1.
Substrate profiles of R. ruber KstDs expressed an analyzed in cell-free extracts of R. erythropolis
| Substrate | KstD1 | KstD2 | KstD3 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rel. act % | Km (µM) | RCE | RCE/RCEAD | Rel. act % | Km (µM) | RCE | RCE/RCEAD | Rel. act % | Km (µM) | RCE | RCE/RCEAD | |
| AD | 100.0 ± 11.6 | 34.2 ± 3.8 | 2.92 | 1.00 | 100.0 ± 11.8 | 40.1 ± 8.7 | 2.60 | 1.00 | nd | nd | ||
| 9OHAD | 107.4 ± 13.4 | 22.1 ± 7.0 | 4.84 | 1.66 | 29.8 ± 6.5 | 543.2 ± 77.8 | 0.05 | 0.02 | nd | nd | ||
| 4BNC | 52.3 ± 7.4 | 76.1 ± 15.7 | 0.69 | 0.24 | 30.8 ± 7.2 | 38.2 ± 6.6 | 0.81 | 0.31 | nd | nd | ||
| Prog | 89.7 ± 7.9 | 27.9 ± 9.5 | 3.22 | 1.10 | 182.0 ± 7.0 | 33.8 ± 4.9 | 5.38 | 2.07 | 18.6 ± 3.7 | 43.6 ± 2.9 | 0.42 | 0.78 |
| Cort | 20.3 ± 5.8 | 161.6 ± 7.6 | 0.13 | 0.04 | 19.0 ± 3.0 | 374.3 ± 74.5 | 0.05 | 0.02 | nd | nd | ||
| Tes | 134.6 ± 22.6 | 28.8 ± 7.4 | 4.67 | 1.60 | 233.3 ± 23.3 | 107.9 ± 18.5 | 2.16 | 0.83 | nd | nd | ||
| 19OHAD | 39.0 ± 10.6 | 368.8 ± 102.4 | 0.11 | 0.04 | 24.6 ± 7.8 | 347.4 ± 41.7 | 0.07 | 0.03 | nd | nd | ||
| DOC | 67.0 ± 7.4 | 21.6 ± 4.5 | 3.10 | 1.06 | 124.2 ± 17.2 | 42.5 ± 5.8 | 2.92 | 1.12 | 21.6 ± 8.8 | 111.3 ± 4.0 | 0.19 | 0.36 |
| 5α-Tes | nd | nd | 75.2 ± 4.8 | 24.57 ± 7.8 | 3.06 | 1.18 | 100.0 ± 21.9 | 181.1 ± 42.6 | 0.55 | 1.00 | ||
Rel. act: relative activity values. Enzyme activities are expressed as percentage of activity of AD (for KstD1 and KstD2 with 3.2 U/mg and 1.4 U/mg respectively) or 5α-tes (for KstD3 with 0.3 U/mg) that were set as 100%
nd enzyme activity was not detected for this substrate, RCE relative catalytic efficiency given by the ratio Rel. act/km, Prog progesterone, Cort corticosterone, Tes testosterone, 5α-tes 5-alpha-testosterone, 19OHAD 19-hydroxy-4-androstene-3,17-dione, DOC deoxycorticosterone, 4-BNC 4-pregnen-3-one-20β-carboxylic acid