## 2 Results and Discussion
### Molecular Docking Simulation
#### 2.5.2 Investigation of \(\beta\)-Sheet Structure Formation  
It is important to note that one important criterion for determining whether peptides can self-assemble into hydrogelated structures is their tendency toward a \(\beta\)-sheet conformation [22]. Given the fact that the optimal conformation of the FEYNF peptide (Figure 7a) revealed the distribution of the hydrophilic and hydrophobic side chains on the opposite sides of the peptide backbone, it is expected that \(\beta\)-strand formation will occur [58]. In this context, the best pose for FEYNF@FEYNF dimer complex was further investigated considering its protonated form (-NH\({}^{3+}\)). Thus, the modeled peptide-peptide complex carried a net charge equal to (+2) by protonation of one amine group for each peptide chain at the opposite end. The molecular conformation of the protonated dimer complex was then subjected to energy minimization by molecular mechanics theory at the level of the YASARA force field. Consequently, the optimal conformation of the modeled protonated dimer (FEYNF@FEYNF(+2)) is depicted in Figure 8.  
Hence, following energy minimization, the tertiary structure of the peptides forms two \(\beta\)-strands with the same N to C orientation (parallel configuration). The \(\beta\)-strands given  
Figure 8: Optimal conformation of the protonated dimmer (FEYNF@FEYNF(+2)) computed at the level of the YASARA force field, suggesting the self-assembling and gelation pathway of FEYNF toward an \(\beta\)-sheet structure (atom colors: cyan—carbon, blue—nitrogen, red—oxygen, and gray—hydrogen).  
in Figure 8 are mainly formed by the backbone in an extended conformation of the GLU2, TYR3, and ASN4 for chain 1 of the FEYNF peptide. For the second chain, the \(\beta\)-strand starts from the C-(C=O) group of the PHE1 and continues with the GLU2 and TYR3 backbone.  
In the depicted conformation (Figure 8), the amidated FEYNF peptide exhibits the capacity to assume a \(\beta\)-sheet structure, as the two represented \(\beta\)-strands are laterally connected by H-bonds. This phenomenon facilitates the extension of \(\beta\)-sheets with an increase in size, particularly as the oligomer expands, inherently implying the formation of a fibril. To confirm the \(\beta\)-sheet formation in the dimer conformation optimized by molecular mechanics at the level of the YASARA force field (Figure 8), the dihedral (torsion) angles \(\Phi\) (Phi) and \(\Psi\) (Psi) were calculated for each chain, and their values are given in Table 1. The \(\Phi\) torsion angle is characteristic for the N \(-\) C\(\alpha\) bond, while the \(\Psi\) angle corresponds to C\(\alpha-\) C bond (as shown in Figure 1a), both types of bonds being flexible and free to rotate. The values for the torsion angles can lead to the determination of the 3D shape of the polypeptide backbone, in accordance with the Ramachandran plot [59].  
The torsion angles, as outlined in Table 1, validate the existence of an elongated conformation conducive to \(\beta\)-sheet formation. The pair values (\(\Phi\),\(\Psi\)), depicted in Figure S7 (in Supplementary Materials), align with the \(\beta\)-sheet region of the Ramachandran plot [59]. An exception is observed in the case of the pair (\(\Phi_{3}\),\(\Psi_{3}\)) for the FEYNF chain 2. This is attributed to the absence of the ASN4 residue in the \(\beta\)-strand formed within the FEYNF chain 2 (as also observed in Figure 8). However, the amidated FEYNF peptide sequences' \(\beta\)-strand conformation confirm their ability to engage in the self-assembly process, generating hydrogelated architectures with a \(\beta\)-sheet tertiary structure.