Table 1.
The linkers used in the study and the descriptors of their length and flexibility.
| Linker | Length | Flexibility | Comment | |||
|---|---|---|---|---|---|---|
| n of Atoms a | Maximal Length (Distance) b [Å] | Rotatable Bonds c | Rotatable Bonds Fraction d | Φ Index e | ||
|
d-Ala -HN-CH(CH3)-CO- |
3 | 2.4 | 2 | 0.11 | 3.06 | short flexible |
| β-Ala -HN-(CH2)2-CO- |
4 | 3.7 | 3 | 0.17 | 3.84 | short flexible |
| Ahx -HN-(CH2)5-CO- |
7 | 7.4 | 6 | 0.22 | 6.53 | long flexible |
| (Ahx)2 -(HN-(CH2)5-CO-)2- |
14 | 16.1 | 12 | 0.26 | 12.21 | very long flexible |
4AMB
|
7 | 6.4 | 3 | 0.12 | 3.51 | long rigid with aromatic ring |
4APhAc
|
7 | 6.2 | 3 | 0.12 | 3.51 | long rigid with aromatic ring |
| -Pro-Gly- | 6 | 7.7 | 3 | 0.10 | 4.09 | long semirigid (with proline) |
| -(Pro-Gly)2- | 12 | 13.8 | 6 | 0.12 | 7.26 | very long semirigid (with proline) |
a number of atoms (in the shortest path between the termini of the linker), b measured between the terminal nitrogen and carbon atoms, in the fully extended conformation, c number of rotatable bonds, the φ torsion of proline residues and the amide bonds excluded, d fraction of the number of rotatable bonds to the number of all bonds, e Φ Kier flexibility index [22] calculated on Acetyl-linker-amide model systems using the program Dragon [23].