Table 3.

RmtC variant activity

NB, no binding.

RmtC	Antibiotic MIC		30S binding, Kia
	Kanamycin	Gentamicin
	μg/ml		nm
Wildtype	>1024	1024	89.5 [72, 112]
K20E	<2	<2	NB
R50E	<2	<2	977 [651, 1497]
K20E/R50E	<2	<2	NB
H54A	<2	<2	75 [28, 203]
H54E	<2	<2	90 [47, 169]
R68E	256–512	<2	1163 [545, 2969]
K72E	256–1024	64–256	469 [225, 1005]
R68E/K72E	<2	< 2	NB
R211A	1024	128	75 [28, 196]
R211E	4	< 2	62 [21, 188]
K236A	>1024	256–512	85 [47, 156]
K236E	8	< 2	76 [40, 146]
R241A	1024	128	104 [79, 137]
R241E	8	<2	99 [39, 252]
M245A	<2	<2	55 [31, 99]
Loop237–246-A4	<2	<2	63 [35, 114]

^a The values in parentheses are 95% confidence interval for the fit K_i after averaging replicate measurements in each experiment (see Table S2 for further details of K_i determination).