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bioRxiv · 10.1101/2023.10.10.561660

Efficacy of the first bioactive peptide from the pearl

Wu, C.·Yin, Z.·Wang, Y.·Chen, X.·Li, B.·Wang, Q.·Yao, L.·Zhang, Z.·Liu, X.·Zhang, R.
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Abstract

Pearls have high medicinal value. In the present study, we discovered the first bioactive peptide in pearls. The bioactive peptide, KKCHFWPFPW, was a novel angiotensin I-converting enzyme (ACE)-inhibitory peptide derived from the pearl matrix of Pinctada fucata. It was screened and identified using quadrupole time-of-flight mass spectrometry. The molecular weight of the peptide was 1417.5 Da, and its theoretical isoelectric point was 9.31. The half-maximal inhibitory concentration of the peptide was 4.17M, as determined by high-performance liquid chromatography. The Lineweaver-Burk plot showed that this peptide competitively inhibited ACE activity. As the peptide concentration increased, the ACE inhibition rate also increased. The molecular docking was simulated using Maestro 2022-1 Glide software to understand the potential mechanisms underlying the ACE-inhibitory activity of KKCHFWPFPW. These results indicated that the peptide from the P. martensii pearl matrix might be a potential source of antihypertensive peptides.

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Wu, C., Yin, Z., Wang, Y., Chen, X., Li, B., Wang, Q., Yao, L., Zhang, Z., Liu, X., Zhang, R.. 2023-10-10. Efficacy of the first bioactive peptide from the pearl. https://doi.org/10.1101/2023.10.10.561660

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