Five umami peptides (RR-12, LD-11, GY-11, SM-14, TL-14) from shrimp juice stably bind T1R1/T1R3 receptors

Umami peptides are crucial for enhancing food flavor and have broader implications for appetite regulation, metabolic health, and even cognitive function by signaling to the orbitofrontal cortex. Despite their potential for industrial applications, efficient high-throughput screening of these microbiota-derived peptides remains a significant challenge. Current methods often lack the integration of multi-omics analysis with in silico screening, creating a gap in understanding the molecular mechanisms behind flavor superiority and peptide-receptor interactions. This study addresses this by combining advanced computational and analytical techniques to identify key umami peptides and their binding to the T1R1/T1R3 taste receptor.

Researchers investigated three shrimp juices (ZG, TG, and 30d fermented) using a multi-omics approach to identify key umami peptides. They employed flavoromics to assess flavor complexity and harmony, followed by ultrafiltration and sensory evaluation to pinpoint the 1-3 kDa fraction as the core taste-active component. An integrated workflow combining machine learning and molecular docking was then used to screen for umami peptides with the lowest binding energies to the T1R1/T1R3 receptor. Finally, molecular dynamics simulations were conducted to confirm the stability and interaction mechanisms of the identified peptides with the receptor.

The 30d fermented shrimp juice exhibited superior flavor complexity and harmony, with umami amino acids constituting 25%-27% of its composition. Ultrafiltration and sensory evaluation confirmed the 1-3 kDa fraction as the primary contributor to the umami taste. Through machine learning and molecular docking, five specific umami peptides—RR-12, LD-11, GY-11, SM-14, and TL-14—were identified as having the lowest binding energies to the T1R1/T1R3 receptor. Molecular dynamics simulations further validated these findings:

Four of the five identified peptides (RR-12, LD-11, GY-11, and SM-14) demonstrated stable binding to the T1R1/T1R3 receptor primarily through hydrogen bonds, providing molecular-level insight into their interaction mechanisms. This confirms the computational predictions and highlights specific peptides responsible for the umami taste.