Table 1. Kinetics of aggregation of full-length natural and designed CT variants.

Peptide	Helical content*	Predicted ln(k′/k)†	Observed ln(k′/k)	Predicted ln(kagg), S−1‡	Observed ln(kagg), S−1	In(Tlag), S§	ΔA340	% recovery¶
hCT	0.17	0	0	−10.2	−7.6 ± 0.2	6.9 ± 0.2	1.9 ± 0.3	0.7 ± 0.2
sCT	0.75	−10.5	−0.3	−12.6	−7.9 ± 0.3	8.3 ± 0.1	0.8 ± 0.2	7.0 ± 2.0
6CHR	2.19	−5.6	−1.1	−11.3	−8.7 ± 0.3	11.6 ± 0.7	2.4 ± 0.3	0.8 ± 0.2
5P	0.63	−11.4	−2.8	−12.8	−10.4 ± 1.4	9.9 ± 0.7	0.4 ± 0.2	32.0 ± 6.0
6S	0.69	−14.0	−4.5	−13.5	−12.2 ± 0.9	11.3 ± 1.2	0.2 ± 0.1	74.0 ± 5.0

Each measurement presented is the mean of at least four different experiments performed on different days, and each consisting of five replicates, along with the standard deviation. Aggregation was also monitored by thioflavin-T binding and TEM analysis (supporting information).

^*Intrinsic helical propensity (in %) was calculated with AGADIR (48) using the appropriate experimental conditions.

^†Calculated as described (26).

^‡Calculated using an extended version of the algorithm described in Chiti et al. (26) as reported elsewhere (27, 28), including sequence patterns that favour aggregation (49), and predicts absolute aggregation rates for any sequence from a random-coil state (www.amyloidfibril.com).

^§T_lag is a descriptor of the lag phase, and corresponds to the time taken to reach 10% of the final amplitude of each kinetic trace.

^¶Recovery was estimated by amino acid analysis of the different samples after sedimentation at 13,000 × g and filtering through a 0.2-μm filter.