Table 2

Comparative glucuronidation activities for UGT2B15^*1 and UGT2B15^*2

Substrate	Pooled HLM Activity	UGT2B15^*1 Activity		UGT2B15^*2 Activity
Substrate	pmol/min/mg	pmol/min/mg	% HLM	pmol/min/mg	% UGT2B15^*1^2-a
S-Oxazepam	32 ± 2	3.4 ± 0.3	9.9 ± 0.8	0.21 ± 0.08	20 ± 5
Eugenol	7271 ± 1266	229 ± 45	3.2 ± 0.6	10 ± 5	15 ± 5
Naringenin	2856 ± 258	87 ± 6	3.0 ± 0.2	2.2 ± 1.4^2-b	8 ± 3
4-Methylumbelliferone	3182 ± 277	152 ± 8	4.8 ± 0.3	13 ± 5	29 ± 6
Androstane-3a-diol	1763 ± 144	83 ± 10	4.7 ± 0.5	5.9 ± 1.5^2-b	23 ± 4
Dihydrotestosterone	934 ± 190	29 ± 3	3.1 ± 0.5	5.9 ± 1.7^2-b	67 ± 13

Glucuronidation activities for five different substrates were determined as described in Materials and Methods using pooled HLMs and UGT2B15^*1 and UGT2B15^*2 stably expressed in HEK-293 cells. Shown are the mean values ± S.D. of triplicate determinations. In addition to absolute values, activities are given as a percentage of HLM activity (for UGT2B15^*1) and as a percentage of UGT2B15^*1 (for UGT2B15^*2).

↵2-a Corrected for 3.3 times higher immunoreactive UGT2B15 protein in UGT2B15*1 compared with UGT2B15*2 microsomal preparations.
↵2-b These activities for UGT2B15*2 were close to the quantitation limit of the assay (1 pmol/min/mg protein).