A Novel Heptapeptide with Tyrosinase Inhibitory Activity Identified from a Phage Display Library

Abstract

Peptidic inhibition of the enzyme tyrosinase, responsible for skin pigmentation and food browning, would be extremely useful for the food, cosmetics, and pharmaceutical industries. In order to identify novel inhibitory peptides, a library of short sequence oligopeptides was screened to reveal direct interaction with the tyrosinase. A phage displaying heptapeptide (IQSPHFF) was found to bind most strongly to tyrosinase. The inhibitory activity of the heptapeptide was evaluated using mushroom tyrosinase. The results showed that the peptide inhibited both the monophenolase and diphenolase activities of mushroom tyrosinase with IC values of 1.7 and 4.0 mM, respectively. The heptapeptide is thought to be a reversible competitive inhibitor of diphenolase with the inhibition constants (Ki) of 0.765 mM. To further investigate how the heptapeptide exerts its inhibitory effect, a docking study between tyrosinase and heptapeptide was performed. The simulation showed that the heptapeptide binds in the active site of the enzyme near the catalytically active Cu ions and forms hydrogen bonds with five histidine residues on the active site. Phage display technology is thus a useful approach for the screening of potential tyrosinase inhibitors and could be widely applicable to a much wider range of enzymes.

Naturally occurring and synthetic peptides: Efficient tyrosinase inhibitors

“…This peptide was able to chelate copper ions, and molecular docking study demonstrated the formation of hydrogen bonds between IQSPHFF and tyrosinase: Lys229, Gly250, and Ser276. The safety of the peptide was proven by the evaluation at the concentration range of 4.5–1152.0 μmol/L toward A375 melanoma cells 51 …”

Isolation and Identification of Tyrosinase-Inhibitory and Copper-Chelating Peptides from Hydrolyzed Rice-Bran-Derived Albumin

“…23 Some synthetic short peptides appear to show inhibitory activity against tyrosinase. 4,7,24 Some oligopeptides 25,26 and squid collagen hydrolysate 27 that showed tyrosinase-inhibitory effects have been suggested as cosmetic agents. Bioactive peptides are small protein fragments that have biological activity after they are released from proteins by hydrolytic treatment.…”

Buffalo cheese whey hydrolyzed with Alcalase as an antibrowning agent in minimally processed apple

“…Histidine residues are present in peptides with high PPO inhibitory capacity, along with residues of phenylalanine, cysteine, tryptophan, tyrosine and arginine. The presence of phenylalanine residues (which are structurally similar to tyrosine, a PPO substrate) in the peptide chain would allow its accommodation and formation of a strong interaction with the active site of the enzyme, which would cause competitive inhibition (Puangphet et al 2015;Nie et al 2017). Fragments of proteins (peptides) containing cysteine and/or phenylalanine residues along with apolar amino acid residues, such as valine, alanine, leucine, histidine and tryptophan, had their inhibitory power increased, since hydrophobicity would facilitate their entry and obstruction on the site of PPO, since it is also apolar (Schurink et al 2007;Noh et al 2009;Campas-Ríos et al 2012;Nie et al 2017).…”

“…The presence of phenylalanine residues (which are structurally similar to tyrosine, a PPO substrate) in the peptide chain would allow its accommodation and formation of a strong interaction with the active site of the enzyme, which would cause competitive inhibition (Puangphet et al 2015;Nie et al 2017). Fragments of proteins (peptides) containing cysteine and/or phenylalanine residues along with apolar amino acid residues, such as valine, alanine, leucine, histidine and tryptophan, had their inhibitory power increased, since hydrophobicity would facilitate their entry and obstruction on the site of PPO, since it is also apolar (Schurink et al 2007;Noh et al 2009;Campas-Ríos et al 2012;Nie et al 2017). Cysteine residues in these peptides probably follow a mechanism of action similar to that of sulfur compounds, such as sulfites and L-cysteine, which participate in the stabilization of o-quinones via nucleophilic addition or reduction reactions (Campas-Ríos et al 2012;Puangphet et al 2015).…”

“…These peptides could act in both the enzymatic and chemical phases of enzymatic browning. In the first phase, they would act as inhibitors of polyphenol oxidase (PPO) by immobilizing the substrate, while in the second phase, they would stabilize o-quinones, blocking subsequent reactions that led to formation of melanins and color changes in the plant surface (Altunkaya 2011;Abubakr 2016;Nie et al 2017).…”