Modification of a Novel Umami Octapeptide with Trypsin Hydrolysis Sites via Homology Modeling and Molecular Docking

Abstract

Increasing the copy number of peptides is an effective method to genetically engineer recombinant expression and obtain umami peptides in large quantities. However, the umami taste value of multicopy number umami peptides is lower than the single ones, thus limiting the industrial application of recombinantly expressed umami peptides. With aims to solve this problem, modification of an umami beefy meaty peptide (BMP) with trypsin hydrolysis sites was carried out via homology modeling and molecular docking in this study. A total of 1286 modified peptide sequences were created and molecularly simulated for docking with the homology modeling-constructed umami receptor (T1R1/T1R3), and 837 peptides were found to be better docked than the BMP. Afterward, the MLSEDEGK peptide with the highest docking score was synthesized. And umami taste evaluation results demonstrated that this modified peptide was close to that of monosodium glutamate (MSG) and BMP, as confirmed by electronic tongue and sensory evaluation (umami value: 8.1 ± 0.2 for BMP; 8.2 ± 0.3 for MLSEDEGK peptide). Meanwhile, mock trypsin digestion of eight copies of MLSEDEGK peptide results showed that the introduced digestion sites were effective. Therefore, the novel modified BMP in this study has the potential for large-scale production by genetic engineering.

Sensory-Guided Isolation, Identification, and Active Site Calculation of Novel Umami Peptides from Ethanol Precipitation Fractions of Fermented Grain Wine (Huangjiu)

“…There are 22 peptides with the greatest potential umami taste according to the machine learning prediction tools (BIOPEP-UWM, Umami_PREL, Umami_YYDS). The MolProbity Ramachandran plot (Figure S1) showed that the stereochemistry of the built receptor model residues was reasonable, with 93.7% in the favored area and 98.7% in the allowed area, similar to the results of Cheng et al [33]. From the docking results (Table S1), ten peptides with intensities larger than 5 × 10 6 and binding energies lower than −8.9 kcal/mol were selected for solid-phase synthesis and sensory evaluation.…”

Integration of cloud-based molecular networking and docking for enhanced umami peptide screening from Pixian douban

“…The composition of Pixian Douban (PXDB), which includes lipids, polyphenols, and various other components ( Yang et al, 2021 ), presents a significant challenge for peptide identification in these samples. To address this challenge, MCX solid-phase columns were utilized to enrich peptides and reduce impurities, as previously described ( Cheng et al, 2023 ). Furthermore, FBMN employs advanced algorithms to swiftly filter and process large datasets obtained from multidimensional high-resolution mass spectrometry.…”

“…This affinity is influenced by the closed conformation of T1R1 ( Fig. S2 B), which results in a less accessible binding cavity ( Cheng et al, 2023 , Dang et al, 2019 , López Cascales et al, 2010 ).…”

Comparison of the taste mechanisms of umami and bitter peptides from fermented mandarin fish (Chouguiyu) based on molecular docking and electronic tongue technology

“…4 The peptides with a higher proportion of E and D possess more umami intensity. 5 Sensory evaluation shows that a strong umami taste is found in umami peptides with the structures of EE, 6 EDE, 7 DEE, and DD. [8][9][10] Besides, more hydrophobic amino acid residues in peptides tend to give a bitter taste, and the peptides made of hydrophobic amino acid residues are more bitter than the mixtures of these free amino acids.…”