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 - DFBPOPIO0004(Opioid peptide)

DFBP ID	DFBPOPIO0004
Peptide sequence	YIPIQYVLSR
Type	Native peptide
Peptide/Function name	Opioid peptide, Casoxin C

Function-activity relationship

Main bioactivity	Opioid activity
Otheir bioactivity	ACE-inhibitory activity ^[D1], Immunomodulatory activity ^[D2], Ileum contracting activity ^[D3], Multifunctional activity ^[D4]

Calculated physicochemical properties

Three-letter amino acid

Tyr-Ile-Pro-Ile-Gln-Tyr-Val-Leu-Ser-Arg

Single-letter amino acid

YIPIQYVLSR

Peptide length

Peptide mass

Experimental mass	Theoretical mass
N.D	1251.47 Da ^c

Net charge

0.00 ^c

Isoelectric point (pI)

9.59 ^c

IC₅₀

N.D

pIC₅₀

N.D

GRAVY

0.4000^c

Hydrophilic residue ratio

50%^c

Peptide calculator

Peptide source & Food-borne protein(s) search

Classification	Animal
Organism/Source	Bovine milk protien^[2]
Precursor protein	κ-Casein
Residue position	f(25-34)
Precursor protein(s) search	Source.1: DFBPPR7686 ---- Milk proteins ---- Kappa-casein Source.2: DFBPPR7695 ---- Milk proteins ---- Kappa-casein Source.3: DFBPPR7715 ---- Milk proteins ---- Kappa-casein Source.4: DFBPPR8492 ---- Milk proteins ---- Kappa-casein
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

The IC₅₀ value of casoxin C was 50 nM the radioreceptor assay in the presence of 1 nM [³H]naloxone. In the guinea pig ileum assay, the A₂ value of casoxin C for μ-selective agonist Tyr-D-Ala-Gly-MePhe-Glyol (DAGO) was 5 μM. As shown in table 1.

Table 1 Opioid antagonist activities of peptide.
Peptide	Receptor assay ^a, IC₅₀, μM	GPI assay ^b, A₂, μM	References
Casoxin C	50	5	－
Casoxin C	Opioid antagonist, this peptide showed a relatively high opioid antagonistic activity in comparison to the esterified peptides (IC₅₀ = 400.0 umol/l) and has been characterized as μ-type ligands.		[2]

^a Radioreceptor test performed in presence of 1 nM [³H]naloxone.
^b Concentration of opioid antagonist to make the IC₅₀ value of μ-receptor specific opioid agonist Tyr-D-Ala-Gly-MePhe-Glyol (DAGO) two-fold in the guinea pig ileum assay.

Specific target protein(s)

Specific Target Protein(s):
Mu-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)N[C@@]([H])([C@]([H])(CC)C)C(=O)N1[C@@]([H])(CCC1)C(=O)N[C@@]([H])([C@]([H])(CC)C)C(=O)N[C@@]([H])(CCC(=O)N)C(=O)N[C@@]([H])(Cc1ccc(O)cc1)C(=O)N[C@@]([H])(C(C)C)C(=O)N[C@@]([H])(CC(C)C)C(=O)N[C@@]([H])(CO)C(=O)N[C@@]([H])(CCCNC(=N)N)C(=O)O

Preparation method

Mode of preparation	Enzymatic hydrolysis
Enzyme(s)/starter culture	κ-Casein was digested with trypsin at 37 ℃.

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]	DFBPACEI0350
[D2]	DFBPIMMU0051
[D3]	DFBPICPE0002
[D4]	DFBPMUFU0107

BIOPEP-UWM

[D5]

3213, 3215, 3216, 3495

APD

[D6]

BioPepDB

[D7]

MBPDB

[D8]

Reference(s)

Primary literature	Chiba H, Tani F, Yoshikawa M. Opioid antagonist peptides derived from kappa-casein. J Dairy Res. 1989;56(3):363-6. PMID: 2760302 DOI: 10.1017/s0022029900028818
Other literature(s)	[1] Park Y W. Bioactive Components in Milk and Dairy Products[M]. 2009. [2] Meisel H, Fitzgerald R J. Opioid peptides encrypted in intact milk protein sequences.[J]. British Journal of Nutrition, 2000, 84(S1):27-31. [3] Meisel H. Overview on Milk Protein-derived Peptides[J]. International Dairy Journal, 1998, 8(5–6):363-373. [4] Kostyra E, Sienkiewiczszłapka E, Jarmołowska B, et al. Opioid peptides derived from milk proteins.[J]. Polish Journal of Food & Nutrition Sciences, 2004. [5] Yoshikawa M., Tani F., Shiota H., Usuñ H., Suganuma H., Usuñ K., Kurahashi K., Chiba H., Casoxin D an opioid antagonist/ileum-contracting/vasorelaxing peptide derived from human α_s1-casein. 1994, in: β-Casomorphins and Related Peptides: Recent Developments (eds. Brantl V., Teschemacher H.). VCH, Weinheim, pp. 43–48.
PubDate	1989