Table 1.

Salt-bridge distances between TnI and actin-tropomyosin at less than 5 Å separation. Distances were measured between NH₃⁺ hydrogen atoms on lysine and arginine sidechains and neighboring COO⁻ oxygen atoms of aspartate and glutamate.

Domain	Tnl Residue	Actin Residue	Tropomyosin Residue	Salt Bridge Distance in Å
Inhibitory peptide	LYS 138	GLU 167		1.74
	ARG 145	ASP 25		1.97
	ARG 146	GLU 2		1.92
		ASP 24		1.92
	ARG 148	GLU 334		1.81
			GLU 163	1.96
Switch peptide	ASP 152		ARG 160	1.86
	ARG 162		GLU 150	1.86
		ASP 56		4.55
Helix H4	GLU 165	LYS 61		3.26
	ARG 170		GLU 139	1.86
	LYS 174		GLU 139	1.63
	LYS 177	ASP 25		1.75
	GLU 182		ARG 125	3.84
	GLU 184	ARG 28		1.91
C-terminal	ARG 186	GLU 2		4.67
	GLU 187	ARG 28		4.29
	ARG 192		GLU 114	1.84
	ASP 196		ARG 101	4.76
			ARG 105	1.87
	GLU 202		ARG 91	1.81
	ARG 204	ASP 25		4.02
	LYS 205		GLU 97	1.84