TABLE 1.

Mechanical properties of mutant Spy0128 domains lacking isopeptide bonds

The experimental histograms were fitted to Gaussian curves (Figs. 2 and 3). The mean value is presented in the table. Errors are given by the standard deviation of the Gaussian fit.

Construct	ΔLc,a I27	Fu,b I27	ΔLc, Spy0128, Nt	Fu, Spy0128, Nt	ΔLc, Spy0128, Ct	Fu, Spy0128, Ct
	nm	pN	nm	pN	nm	pN
I278 (from Ref. 25)	28.4 ± 0.3	204 ± 26
(I27-Spy0128-E117A)2-I27	28.7 ± 0.7	201 ± 29	52 ± 2	172 ± 33
(I27-Spy0128-E258A)2-I27	29.2 ± 0.8	204 ± 30			50 ± 2	250 ± 96

^a ΔL_c, increment in contour length.

^b F_u, unfolding force.