Table 1

Dearylation and desulfuration activities toward chlorpyrifos in HLM, RLM, or MLM

	Desulfuration		Dearylation
	K_{m_app}	V_{max_app}	V_{max_app}/K_{m_app}	K_{m_app}	V_{max_app}	V_{max_app}/K_{m_app}
	μM	nmol/mg protein/min		μM	nmol/mg protein/min
HLM	30.2 ± 1.7	0.4 ± 0.1	0.01	14.2 ± 2.2	0.7 ± 0.1	0.05
RLM	6.1 ± 1.1^**	1.0 ± 0.2^*	0.17	4.8 ± 1.8^*	2.1 ± 0.4^**	0.43
MLM	24.4 ± 2.4	0.7 ± 0.1	0.03	14.9 ± 3.0	2.7 ± 0.1^**	0.18

Activities are expressed as mean ± S.E.M. (n = 3 determinations), means in RLM (pooled from three male rats) and MLM (pooled from three male mice) significantly different than HLM (pooled from 10 donors) are indicated by ^*p < 0.05 or ^**p < 0.01.