TABLE 1

Steroid substrate profiles of KshA1N and KshA2N

Steroid substrateaKshA1NKshA2N
Enzyme activitya (nmol min−1 mg−1)Relative activityb (%)Enzyme activity (nmol min−1 mg−1)Relative activity (%)
4-Androstene-3,17-dione (AD)2.3 × 102 ± 21 × 1021001.2 × 102 ± 15 × 102100
4-Androstene-17β-ol-3-one (testosterone)3.1 × 102 ± 17 × 10213590 ± 1075
1,4-Androstadiene-3,17-dione (ADD)6.5 × 102 ± 31 × 1022821.5 × 102 ± 29 × 102125
1,4-Androstadiene-17β-ol-3-one (boldenone)5.8 × 102 ± 47 × 1022521.3 × 102 ± 27 × 102108
1-(5α)-Androstene-17β-ol-3-one1.8 × 102 ± 39 × 1027823 ± 719
1-(5α)-Androstene-3,17-dione2.1 × 102 ± 33 × 1029127 ± 923
5α-Androstane-3,17-dione52 ± 1123NDcND
5β-Androstane-3,17-dione75 ± 1233NDND
5α-Androstane-17β-ol-3-one (androstanolone)42 ± 1518NDND
5α-Androstane-3α-ol-17-oneNDNDNDND
5α-Androstane-3β-ol-17-one (epiandrosterone)NDNDNDND
5-Androstene-3β-ol-17-one (dehydroepiandrosterone)NDNDNDND
9α-Hydroxy-4-androstene-3,17-dione (9-OHAD)NDNDNDND
4-Androstene-3,17-dione-19-ol (19-OHAD)23 ± 1610NDND
1,3,5(10)-Estratrien-3-ol-17-oneNDNDNDND
4-Pregnene-3,20-dione (progesterone)7.7 × 102 ± 49 × 1023351.8 × 102 ± 21 × 102150
11β-Hydrocortisone1.2 × 102 ± 40 × 1025238 ± 1132
23,24-Bisnorchol-1,4-diene-22-oic acid (1,4-BNC)9.8 × 102 ± 55 × 1024262.1 × 102 ± 38 × 102175
4-Cholestene-3-oned (cholesterone)45 ± 721NDND
5-Cholestene-3β-old (cholesterol)NDNDNDND
  • a Specific Ksh activity levels toward substrates were analyzed at 200 μM and represented as means ± standard errors from three independent experiments.

  • b Relative activity signifies the percentage of the activity toward substrates relative to that of AD, which was set at 100%.

  • c ND, no detectable activity toward specific steroid.

  • d Steroid concentration of 25 μM due to the low steroid solubility.