TABLE 1.

ITC results and capillary assays of all 20 amino acids

Amino acid	mcpC mutanta	Capillary assay accumulationb	KDc	ITC KD	McpC E115A mutant	McpC K195A mutant
	% reduced		μm	μm	% reduced	% reduced
Cys	100	28,175 ± 5,408	10	NAd	>99	20
Pro	99	29,119 ± 4,845	1	14	>99	8
Thr	99	30,120 ± 6,375	5.6	21	97	11
Gly	99	13,081 ± 6,440	320	699	94	51
Ser	99	9,395 ± 816	32	90	95	9
Lysh	99	15,500 ± 5,348	1,000	NBe	50	88
Val	98	15,653 ± 6,372	32	154	96	60
Argh	98	12,887 ± 1,574	100	NBe	<1	95
Ala	92	12,225 ± 3,766	0.32	18	97	4
Tyr	92	2,378 ± 701	320	360	95	<1
Glu	89	3,892 ± 2,515	32,000	NBe	98	54
Ile	87	3,355 ± 219	100	1,000	97	67
Meth	79	8,650 ± 2,036	100	NBe	62	91
Trp	78	254 ± 42	3,200	3,700	<1	86
Phe	72	8,713 ± 1,061	320	492	95	77
Leu	70	8,713 ± 1,061	32	72	97	80
Asp	35	3,355 ± 1,061	10,000	NBe	97	51
Glnh	34	1,475 ± 369	32	NBe	55	95
His	27	26 ± 12	3,200	320f	NAg	NAg
Asn	0	0 ± 35	56	NBe	NAg	NAg

^a As previously determined experimentally (3).

^b Strain OI4007 (Δ10 mcp amyE::mcpC). All amino acids were tested at 0.01 m, except for Glu and Asp, which were tested at 0.1 m.

^c As previously determined experimentally (26).

^d Could not be tested.

^e No binding under the conditions tested.

^f Exothermic binding.

^g Accumulation too low.

^h Chemotaxis mediated by an amino acid binding protein.