Table 1.

Results from kinetic analysis of ensemble and single-molecule force experiments

Construct	Linker length, aa	Urea $m_{\mathrm{U}}^{‡}$, M−1	$x_{\mathrm{U}}^{‡}$, nm	$\text{ln}{k}_{\mathrm{U}}^{0\text{pN},0\text{M urea}}$
Ensemble data
Src SH3*	0	0.29 ± 0.04	NA	−2.03 ± 0.38
Free-SH3†	38	0.30 ± 0.04	NA	−1.47 ± 0.31
Free-SH3†	58	0.29 ± 0.02	NA	−1.23 ± 0.15
Free-SH3 L24A†	38	0.28 ± 0.02	NA	1.08 ± 0.13
Single-molecule force data
Free-SH3†	38	0.31 ± 0.23	0.37 ± 0.02§	−2.12 ± 0.16
RNC-SH3¶	38	0.33 ± 0.23	0.37 ± 0.02§	−2.63 ± 0.16
RNC-SH3¶	58	NA	0.37 ± 0.02§	−2.76 ± 0.19
RNC-SH3 L24A¶	38	NA	0.37 ± 0.02§	−1.85 ± 0.18

^*Contains no tags of linkers.

^†Contains N-terminal Avi tag and C-terminal ybbr tag.

^§These values were linked in global analysis.

^¶Contains N-terminal Avi tag and C-terminal SecM sequence.