Table 3. Specific activities of zebrafish SULT1 ST9, SULT3 ST4, and SULT3 ST5 with endogenous and xenobiotic compounds as substrates^a.

Endogenous compounds	SULT1 ST9	SULT3 ST4	SULT3 ST5	Xenobiotic compounds	SULT1 ST9	SULT3 ST4	SULT3 ST5
DHEA	NDb	13.83 ± 0.20	0.58 ± 0.02	17α-Ethynylestradiol	0.08 ± 0.01	0.58 ± 0.02	1.04 ± 0.02
Androstene-3,17-dione	ND	0.40 ± 0.02	0.10 ± 0.01	Caffeic acid	7.53 ± 0.07	ND	ND
17β-Estradiol	0.08 ± 0.01	3.45 ± 0.07	0.08 ± 0.01	Gallic acid	0.77 ± 0.04	ND	ND
Progesteron e	ND	0.28 ± 0.01	ND	Mestranol	ND	0.98 ± 0.07	0.16 ± 0.01
Estrone	0.22 ± 0.01	0.21 ± 0.01	ND	Chrologenic acid	15.29 ± 0.44	ND	ND
Pregnenolone	ND	9.04 ± 0.06	0.06 ± 0.01	β-Naphthylamine	0.38 ± 0.01	0.31 ± 0.01	0.03 ± 0.01
Corticosterone	ND	0.80 ± 0.02	0.14 ± 0.01	β-Naphthol	21.32 ± 0.25	0.14 ± 0.01	0.06 ± 0.01
T3	ND	ND	ND	Butylated hydroxyl anisole	0.12 ± 0.01	0.13 ± 0.01	0.11 ± 0.01
T4	0.51 ± 0.02	0.05 ± 0.01	0.10 ± 0.01

^aSpecific activity refers to nmol substrate sulfated/min/mg purified enzyme. Data represent mean ± S.D. derived from three determinations. The concentration of the substrate used in the assay mixture was 50 μM.

^bND refers to activity not detected. Specific activity determined was lower than the detection limit (estimated to be ∼0.01 nmol/min/mg protein).