Table 1. Hydrolytic activity of Hovi-mEH1 for various epoxide-containing substrates.

Substrate	Structure	Activitya (nmol min−1 mg−1)
c-SO		47.5 ± 6.2
t-SO		n.d.b
t-DPPO		1.3 ± 0.5
14,15-EET		0.36 ± 0.007
JH IIIc		29.3 ± 1.6

^aThe enzyme assays were performed at 30°C in buffer (100 mM sodium phosphate, pH 8.0, for JH III, c-SO, t-SO, and t-DPPO; or 25 mM Bis-Tris, pH 7.0, for 14,15-EET) containing substrate (50 μM for c-SO, t-SO, t-DPPO, and 14,15-EET; or 0.642 to 69.8 μM for JH III), 1% (v:v) ethanol, and 0.1 mg ml⁻¹ BSA. The JH III assays also contained 10 μM OTFP and 2% (v:v) ethanol. The values shown are the mean ± standard deviation of at least three separate experiments. Background hydrolytic activity in negative control experiments was less than 1% of total activity.

^bActivity was not detected at an assay detection limit of 0.01 nmol min⁻¹ mg⁻¹.

^cV_max is shown for JH III.