The binding mechanism of a novel ferrous ion chelating peptide from chicken blood hemoglobin and the bioavailability of the chelate

In this study, chicken blood hemoglobin hydrolysates were subjected to separation and purification. A novel peptide (TAEDKKLIQ) with high ferrous ion chelating activity was identified from chicken blood hemoglobin hydrolysate. The binding mechanism between TAEDKKLIQ and ferrous ions was elucidated using a combination of structural characterization, molecular docking, and molecular dynamics simulation. The results indicated that TAEDKKLIQ formed a monodentate coordination bond with ferrous ions via the carboxyl group on the Asp side chain, exhibiting a single binding site. Furthermore, the stability and cellular activity experiments demonstrated that TAEDKKLIQ-Fe not only exhibited good chemical stability but also surpassed lactoferrin, the conventional iron supplement, in cellular activity. This study provided new scientific evidence for the application of peptides derived from chicken blood in food processing and nutritional fortification systems, and provided theoretical support for developing highly efficient and safe peptide-based iron supplements. • A novel peptide was isolated from chicken hemoglobin and determined to be TAEDKKLIQ. • The chelation ability of TAEDKKLIQ was high, with a chelation rate over 90 %. • The carboxyl group of the Asp side chain provided the monodentate coordination. • The chelation was facilitated by electrostatic interactions. • TAEDKKLIQ-Fe exhibited excellent bioavailability.