Table 2. MICs for Escherichia coli Strains Expressing TEM β-Lactamase Variants^a.

	cefotaxime (μM)
	single mutant	double mutant (+G238S)
wild-type TEM	<0.035	0.141
Suppressor/Stabilizing
M182T	0.070	72.000
M182S	0.070	36.000
Wild-Type-like/Neutral
M182V	<0.035	0.141
M182N	<0.035	0.141
M182C	<0.035	0.281
M182A	<0.035	0.281
Deleterious
M182G	ndb	<0.035
M182P	nd	<0.035
M182I	nd	<0.035
M182L	nd	<0.035
M182F	nd	<0.035
M182W	nd	<0.035
M182Y	nd	<0.035
M182R	nd	<0.035
M182H	nd	<0.035
M182 K	nd	0.070
M182D	nd	<0.035
M182E	nd	<0.035
M182Q	nd	<0.035
M182G	nd	<0.035

^aMIC determination was performed in triplicate. Values are most commonly observed concentration with an error of ± one well, which differ by 2-fold in concentration.

^bNot determined.