Peptide properties

1Top 2Function-activity relationship 3Calculated physicochemical properties 4Peptide source & Food-borne protein(s) search 5Biological/Functional activity & target protein 6Taste properties & Structure 7Preparation method 8Stability & Cytotoxicity 9Additional information 10Database cross-references 11Reference(s)

List of peptide properties

DFBP ID - DFBPOPIO0042(Opioid peptide)

DFBP ID	DFBPOPIO0042
Peptide sequence	YGFLP
Type	Native peptide
Peptide/Function name	Opioid peptide

Function-activity relationship

Main bioactivity	Opioid activity
Otheir bioactivity	ACE-inhibitory activity ^[D1], Multifunctional activity ^[D2]

Calculated physicochemical properties

Three-letter amino acid

Tyr-Gly-Phe-Leu-Pro

Single-letter amino acid

YGFLP

Peptide length

Peptide mass

Experimental mass	Theoretical mass
N.D	595.69 Da ^c

Net charge

0.00 ^c

Isoelectric point (pI)

5.92 ^c

IC₅₀

N.D

pIC₅₀

N.D

GRAVY

0.6600^c

Hydrophilic residue ratio

80%^c

Peptide calculator

Peptide source & Food-borne protein(s) search

Classification	Human
Organism/Source	Human milk
Precursor protein	β-Casein
Residue position	f(59-63)
Precursor protein(s) search	Source.1: DFBPPR2000 ---- Plant proteins ---- Sodium/calcium exchanger NCL1 Source.2: DFBPPR2164 ---- Plant proteins ---- Sodium/calcium exchanger NCL2 Source.3: DFBPPR4837 ---- Plant proteins ---- Protein DEHYDRATION-INDUCED 19 homolog 5 Source.4: DFBPPR7605 ---- Milk proteins ---- Beta-casein Source.5: DFBPPR17137 ---- Animal proteins ---- Interleukin-1 receptor-associated kinase 1 Source.6: DFBPPR19770 ---- Animal proteins ---- Heat shock 70 kDa protein 13 Source.7: DFBPPR20543 ---- Animal proteins ---- Procollagen galactosyltransferase 1 Source.8: DFBPPR15421 ---- Microorganism protein ---- Cytochrome c lysine N-methyltransferase 1
Link-research Inductive analysis	There are no literature reports on the discovery of this sequence in other food-source proteins.

Biological/Functional activity & target protein

Opioid activity

YGFLP showed weak opioid activity. As shown in table 1.

Table 1 Opioid activity of peptides
Peptide	IC₅₀ (uM)			IC₅₀ MVD	Activity	References
	RA^a	GPI^b	MVD^c	IC₅₀ GPI
YGFLP	300	270	> 1000	－	Opioid agonist	－
	Opioid agonist, this peptide showed weak opioid activities and was rather selective for δ-receptors in the presence of peptidase inhibitors [1]					[1]

^a Radioreceptor assay in the presence of 1 nM [³H]naloxone.
^b Guinea pig ileum assay.
^c Mouse vas deferens assay. nd, not determined

Specific target protein(s)

Specific Target Protein(s):
Mu-type opioid receptor
Delta-type opioid receptor

Taste properties & Structure

Bitterness

Literature report	N.D
Bitter prediction tools	Bitter taste ^prediction

SMILES

N[C@@]([H])(Cc1ccc(O)cc1)C(=O)NCC(=O)N[C@@]([H])(Cc1ccccc1)C(=O)N[C@@]([H])(CC(C)C)C(=O)N1[C@@]([H])(CCC1)C(=O)O

Preparation method

Mode of preparation	Synthesis peptide
Enzyme(s)/starter culture	Peptide was synthesized by a solid-phase method on chloromethyl resin.

Stability & Cytotoxicity

Peptide stability

Literature report:	N.D
EHP-Tool:	Enzymatic Hydrolysis Prediction Tool (EHP-Tool)

Peptide cytotoxicity

Literature report:	N.D
Prediction:	ToxinPred

Additional information

N.D

Database cross-references

DFBP

[D1]	DFBPACEI0381
[D2]	DFBPMUFU0406

[D3]

[D4]

[D5]

[D6]

Reference(s)

Primary literature	Yoshikawa, M., Tani, F., Yoshimura, T., Chiba, H. Opioid Peptides from Milk Proteins. Agricultural and Biological Chemistry. 2014, 50, 2419-21. DOI: 10.1080/00021369.1986.10867763
Other literature(s)	[1] Meisel H, Fitzgerald R J. Opioid peptides encrypted in intact milk protein sequences [J]. British Journal of Nutrition, 2000, 84(S1):27-31. [2] Kohmura M, Nio N, Kubo K, et al. Inhibition of angiotensin-converting enzyme by synthetic peptides of human. BETA.-casein[J]. Journal of the Agricultural Chemical Society of Japan, 1989, 53(8):2107-2114.
PubDate	2014