TABLE 2

Kinetic analysis of N-glucuronidation in UGT1A4- and UGT2B10-overexpressing cell homogenates and HLMs of TSNAs

	TSNA	V_max	K_M	V_max/K_M	Normalized V_max/K_M UGT2B10/UGT1A4 Ratio^a
		pmol/min/mg total protein	mM	nl/min/mg total protein
UGT1A4	NNAL	99 ± 27^b	22.79 ± 3.83	4.35 ± 0.96	Referent
	NNN	182 ± 43	26.24 ± 14.27	7.70 ± 2.13	Referent
	NAB	166 ± 22	5.37 ± 1.61	32.1 ± 6.63	Referent
	NAT	124 ± 4	3.31 ± 0.23	37.6 ± 2.31	Referent
UGT2B10	NNAL	7.55 ± 0.37	3.62 ± 2.31	3.07 ± 2.13	3.0
	NNN	7.66 ± 1.63	1.18 ± 0.27	6.60 ± 1.08	3.6
	NAB	41.09 ± 11.28	0.28 ± 0.00	147 ± 42.0	19
	NAT	52.65 ± 14.99	0.22 ± 0.06	242 ± 2.86	27
HLM^c	NNAL	259 ± 42	0.85 ± 0.42	348 ± 163
	NNN	1400 ± 60	3.17 ± 0.37	446 ± 61
	NAB	2476 ± 621	0.20 ± 0.03	12,806 ± 5069
	NAT	2593 ± 457	0.16 ± 0.01	16,227 ± 2852

↵ a V_max/K_M normalized by mRNA expression levels in UGT1A4- and UGT2B10-overexpressing HEK293 cell lines using GAPDH as an expression control
↵ b Data are expressed as the mean ± S.D. of three independent experiments
↵ c HLM from one individual