Table 1.
Comparison of kinetic parameters for wild-type IAPP and aromatic to leucine mutants. Experiments are performed at 25 °C, pH 7.4 20 mM Tris-HCl, 2% (v/v) HFIP with constant stirring.
| peptide | Lag timea (sec) | t50b (sec) | Lag time
|
t50
|
|---|---|---|---|---|
| wild-type Lag time | t50 of wild-type | |||
| Wild-type | 1310±280c | 1470±280 | ||
| F15L-IAPP | 490±50 | 640±40 | 0.4±0.1d | 0.4±0.1 |
| F23L-IAPP | 2230±220 | 2470±220 | 1.7±0.4 | 1.7±0.3 |
| Y37L-IAPP | 2790±90 | 4160±100 | 2.1±0.5 | 2.8±0.5 |
| F15LF23L-IAPP | 5100±60 | 5850±30 | 3.9±0.8 | 4.0±0.8 |
| F15LY37L-IAPP | 1790±140 | 2650±100 | 1.4±0.3 | 1.8±0.4 |
| F23LY37L-IAPP | 9670±150 | 10600±500 | 7.4±1.6 | 7.2±1.4 |
| 3XL | 9210±260 | 10950±250 | 7.0±1.5 | 7.4±1.4 |
a
The lag time is defined here as the time required to reach 10% of the final fluorescence change in the thioflavin-T assays.
b
t50 is the time required to reach 50% of the final fluorescence change in the thioflavin-T assays.
c
The quoted uncertainty is the standard deviation.
d
The uncertainty was determined by standard propagation of error.