A rapid selection strategy for umami peptide screening based on machine learning and molecular docking

Revealing the Secret of Umami Taste of Peptides Derived from Fermented Broad Bean Paste

“…Flavor peptides mostly exhibit not a single taste but a comprehensive expression of a mixture of multiple flavors . Almost every peptide contains sweetness, which was similar to the conclusion of Li et al and Saites et al that umami-tasting substances could potentiate the perception of sweetness. , Sourness and astringence were detected in some synthetic peptide samples, which may come from the presence of those residual acidic amino acids during the synthesis of the target peptide. , Additionally, sensory panels were perceived to have a slightly salty taste. Among all peptides, NK-7, EK-12, and LR-5 possessed a strong umami taste, and DK-6 displayed a slight umami taste.…”

“…Several critical residues including Glu301, Ala302, Thr305, Ser104, His145, and His387 have been reported in the T1R3–peptide complex, where the umami peptides were derived from Trachinotus ovatus , Ruditapes philippinarum , chouguiyu, and Atlantic cod . According to a recent study, Ser146 in T1R3 was also considered a key binding residue for the umami peptide . The results of the binding sites described above may provide a valuable basis for the accurate prediction of unknown peptides.…”

“…When comparing the docking energy ranking with the sensory profile, a significant change in position was observed for LR-5 and SR-7, while the other peptides were similar. Combined with the results of Figure a and Table , it can be concluded that the intensity of the umami taste cannot be completely judged by the binding energy value, the purpose of the molecular docking study was to identify the binding site of the umami peptide. , …”

“…When the negatively charged acidic amino acids are at the C-terminus and the positively charged basic groups are at the N-terminus, peptides have the umami taste characteristic . Residues containing the C-terminal amino acids lysine (K) and arginine (R) could promote the expression of umami, which affected its interaction with taste receptors and consequently its taste intensity. , Thus, 10 peptides were identified with 5–12 amino acids (PKALSAFK, PK-8; NKHGSGK, NK-7; VIFGETLTGR, VR-10; AFQWTAWR, AR-8; SADETPR, SR-7; SDRKIPEK, SK-8; EIKKAALDANEK, EK-12; DALAHK, DK-6; LDDGR, LR-5; GHENQR, GR-6), and they were not retrieved from the database BIOPEP-UWM. These peptides all included the umami-related amino acid residues mentioned above.…”

“…The FBBP samples were prepared following the procedure reported by Li et al and Yang et al , with some modifications. In brief, 250 g of an FBBP sample was homogenized with 750 mL of deionized water (1:3, w/v) using a blender (Midea, China).…”