TABLE 2.
Time constants derived from the global fitting routine for the transient absorbance changes of AMPB and AMPB peptides for both isomerization directions
| Time constants (ps)
|
||||||||
|---|---|---|---|---|---|---|---|---|
| Sample | trans → cis | cis → trans | ||||||
| AMPB | 0.47 | 1.6 | 7.9 | 0.25 | 2.9 | 12 | ||
| l-AMPB | 0.58 | 8.8 | 93 | 0.25 | 1.3 | 10 | 58 | |
| c-AMPB | 1.7 | 9.6 | 120 | 0.19 | 1.3 | 9.3 | 180 | |
| bc-AMPB | 0.3 | 1.6 | 10 | 0.28 | 5.4 | 100; 1000 | ||
The time constants with similar amplitude spectra (see Fig. 6) are placed in the same column. The time constants result from multiexponential modeling of the observed absorption transients. Usually, three to four time constants were sufficient for a satisfactory global fit. Nevertheless, it should be kept in mind that a sum of exponential functions is only a rough approximation of the underlying molecular processes.