Heterologous expression of a recombinant ACE inhibitory peptide LYPVK and its potential antihypertensive action mechanism

Enzymatic hydrolysis approach is commonly employed for preparation of active peptides, while the limited purity and yield of produced peptides hinder further development of action mechanisms. This study presents the biotechnological approach for the efficient production of recombinant angiotensin converting enzyme (ACE) inhibitory peptide LYPVK and investigates its potential antihypertensive action mechanism. DNA encoding sequence of recombinant peptide was designed to form in tandem, which was expressed in Escherichia coli BL21 (DE3). The expressed tandem repeat protein with molecular weight of 13.4 kDa was verified by high performance liquid chromatography (HPLC) and amino acid composition. Subsequently, LYPVK was generated following His-tag removal and trypsin-mediated cleavage of the purified protein, which was performed HPLC and liquid chromatography-mass spectrometry (LC-MS) analysis. LYPVK exhibited an IC50 value of 10.6 ± 0.86 μg/mL, demonstrating a non-competitive mode of action and resistance to gastrointestinal enzyme hydrolysis and heat conditions. Molecular docking results showed that LYPVK interacted with ACE through conventional hydrogen bonds and hydrophobic interactions. Except for ACE, ALB, SRC, PPARG, and MMP9 are identified as potential key targets for its antihypertensive activity by network pharmacological analysis. This study provides a promising biotechnological approach for the preparation of active peptides with high purity and yield.