Table 1.

Dissociation constants of Ca²⁺ and TRTK-12 from Ca²⁺-S100B or Ca²⁺-S100B-target complexes^a

	Ca EF2KD (µM)b	Ca EF2 + TRTKKD (µM)c	TAMRA-TRTKKD (µM)d	TRTKKD (µM)e
S100B	56 ± 9 (5)f	12 ± 10 (5)g	1.2 ± 0.2 (2)g	2.9 ± 0.5 (2)g
D61NS100B	412 ± 67 (3)	29 ± 1.2 (3)	1.4 ± 0.2 (2)	2.1 ± 0.7 (2)
D63NS100B	50 ± 8.6 (3)	10 ± 2.2 (4)	0.47 ± 0.04 (2)	3.7 ± 0.3 (2)
D65NS100B	968 ± 171 (3)	73 ± 4.4 (3)	0.34 ± 0.16 (2)	1.6 ± 0.4 (2)
E72AS100B	471 ± 133 (4)	18 ± 3.7 (4)	0.33 ± 0.11 (2)	4.8 ± 1.1 (2)

^aValues in parenthesis are the number of experiments performed.

^bDissociation constants of Ca²⁺ from the tight site (EF2) of S100B and S100B mutants; ^{Ca EF2}K_D = [S100B][Ca²⁺]/[S100B-Ca²⁺]^EF2

^cDissociation constants of Ca²⁺ from the tight site (EF2) of S100B and ^D63NS100B in the presence of TRTK-12 peptide.

^dDissociation constants of TAMRA-TRTK-12 from Ca²⁺-S100B and Ca²⁺- ^D63NS100B as measured directly from fluorescence polarization.

^eDissociation constants of TRTK-12 from Ca²⁺-S100B as measured from competition experiments with TAMRA-TRTK-12.

^fValues reported by Rustandi et al.¹⁴

^gValues reported by Charpentier et al.⁷