# Discovery and mechanistic profiling of novel kokumi peptides from Wuding chicken soup

## TL;DR

This study discovers four new kokumi peptides in Wuding chicken soup and explains how they interact with a taste receptor.

## Contribution

The first discovery of kokumi peptides in Wuding chicken soup and their binding mechanism with CaSR.

## Key findings

- Fifteen kokumi peptides were identified, with four selected for detailed analysis.
- Key amino acid residues involved in peptide-CaSR interaction were identified.
- Hydrophobic interactions and hydrogen bonding were the main binding forces.

## Abstract

This study aims to identify potential kokumi peptides in Wuding chicken soup. To enrich oligopeptides, the preparation process was optimized, and a combined approach using ultrafiltration and gel filtration chromatography was employed for separation and purification. Sensory analysis was then integrated to screen and identify kokumi peptides. And an in-depth study was conducted on the binding mechanism of peptides and calcium-sensing receptors (CaSR). Fifteen kokumi peptides were identified, of which four (LPVPAFN, SAAPAAPVPA, VPAFNVING, and AGFAGDDAPR) were selected for detailed analysis. The primary active sites mediating the interaction between these peptides and the CaSR were identified as Arg 66, Ser 303, Ser 147, Glu 297, and Arg 69, with hydrophobic interactions and hydrogen bonding serving as the predominant binding forces. As the first discovery in Wuding chicken soup, this study establishes a methodological framework for kokumi peptide screening in local chicken varieties and advances structure-activity relationship insights for future applications.

Unlabelled Image

•Four novel kokumi peptides were found in Wuding chicken soup.•Kokumi peptides mainly bind to the A chain of the receptor CaSR.•Arg 66, Ser 303, Ser 147, Glu 297, and Arg 69 were the key amino acid residues.•Hydrogen bonding and hydrophobic interaction were the main binding forces.

Four novel kokumi peptides were found in Wuding chicken soup.

Kokumi peptides mainly bind to the A chain of the receptor CaSR.

Arg 66, Ser 303, Ser 147, Glu 297, and Arg 69 were the key amino acid residues.

Hydrogen bonding and hydrophobic interaction were the main binding forces.