## 2 Materials and Methods  
The dipeptides AH (PubChem ID: 9837455), DA (PubChem ID: 5491963), DG (PubChem ID: 151148), EE (PubChem ID: 439500), ES (PubChem ID: 6995653), EV (PubChem ID: 6992567), VG (PubChem ID: 6993111), which have been described as taste-related peptides and are present in dry-cured ham, were processed for an in silico analysis in order to predict their potential interacting mechanisms with the receptor. The ligand sequences, as well as that from glutamate (E) (PubChem ID: 33032), were obtained in \"sdf\" format from PubChem tool ([[https://pubchem.ncbi.nlm.nih.gov/](https://pubchem.ncbi.nlm.nih.gov/)]([https://pubchem.ncbi.nlm.nih.gov/](https://pubchem.ncbi.nlm.nih.gov/)), accessed on 15 July 2021) [31],and the PDB files were extracted using Discovery Studio Visualizer v20.1.0.19295 software (Dassault Systemes BIOVIA Corp., 2020). The structures of mGluR1 _Rattus norgegicus_ closed-open and open-open conformations, and _Homo sapiens_ open-open conformation (protein data bank ID: 1 EWK, 1 EWK and 3 KS9), in complex with E [32], ligand free and LY341495 antagonist [33], respectively, were downloaded from the Protein Databank (PDB) tool ([[https://www.rcsb.org/](https://www.rcsb.org/)]([https://www.rcsb.org/](https://www.rcsb.org/)), accessed on 15 July 2021) [34].  
Ligand-protein docking simulations were carried out using AutoDock v1.5.6 and AutoDock v4.2.5.1 (Scripps Research Institute) software [35; 36]. The minimum system requirements are Intel 32/64-bit, Pentium/Dual core, Microsoft Windows (98, 2000, XP, Vista, Windows 7)/Linux and Macintosh, 256 MB of minimum RAM, and 200 MB of minimum hard disk space.  
Gasteiger charges and hydrogens were added to all molecules; water molecules and original ligands were also removed from the enzyme, and ligand torsions were detected by AutoDock. Structure data files were converted into the Protein Data Bank partial charge and atom type format.  
Firstly, a preliminary test to obtain more information about the coordinates of the area for screening was carried out. Insights were made by submitting the original receptor PDB archives to ProteinsPlus, and processing the molecule with the tool PoseView ([[https://proteins.plus/](https://proteins.plus/)]([https://proteins.plus/](https://proteins.plus/)), accessed on 15 July 2021) [37; 38] and the web server DoGSiteScorer ([[https://proteins.plus/](https://proteins.plus/)]([https://proteins.plus/](https://proteins.plus/)), accessed on 15 July 2021) [39].  
The definitive Grid Box (60 \(\times\) 60 \(\times\) 60) was centered on one of the mGluR1 binding sites where active residues located, with coordinates X = 11,407, Y = 13,031, and Z = 12,342 for 1 EWK [40; 41], X = 16,958, Y = 28,615, and Z = 45,202 for 1 EWT and X = \(-\)41,815, Y = 9345 and Z = 34,170 for 3 KS9 [42], with a spacing of 0.375 A. Fifty docking runs were performed, using a Lamarchian genetic algorithm between the flexible ligand and rigid receptor, a population size of 150, a maximum of 2,500,000 generations and 2,500,000 evaluations for 50 GA runs. The root-mean-square deviation tolerance was set to 2.0 A for the clustering of docking results. Analysis of the results were conducted by sorting the different complexes with respect to the predicted binding energy. The pose with the lowest binding energy in each case was individually examined, and interactions were processed with online software, Protein-Ligand Interaction Profiler (PLIP) ([[https://plip-tool.biotec.tu-dresden.de/plip-web/plip/index](https://plip-tool.biotec.tu-dresden.de/plip-web/plip/index)]([https://plip-tool.biotec.tu-dresden.de/plip-web/plip/index](https://plip-tool.biotec.tu-dresden.de/plip-web/plip/index)), accessed on 15 July 2021) [43], to validate the interactions; and with ProteinsPlus ([[https://proteins.plus/](https://proteins.plus/)]([https://proteins.plus/](https://proteins.plus/)), accessed on 15 July 2021) [37; 44] to obtain the two-dimensional representations by using the PoseView algorithm [44].