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 - DFBPDPIV0099(DPP IV-inhibitory peptide)

DFBP ID	DFBPDPIV0099
Peptide sequence	PQNIPPL
Type	Native peptide
Peptide/Function name	DPP-IV inhibitory peptide, Anti-diabetic peptide

Function-activity relationship

Main bioactivity	DPP-IV inhibitory activity
Otheir bioactivity	N.D

Calculated physicochemical properties

Three-letter amino acid

Pro-Gln-Asn-Ile-Pro-Pro-Leu

Single-letter amino acid

PQNIPPL

Peptide length

Peptide mass

Experimental mass	Theoretical mass
N.D	777.91 Da ^c

Net charge

0.00 ^c

Isoelectric point (pI)

5.97 ^c

IC₅₀

N.D

pIC₅₀

N.D

GRAVY

-0.5000^c

Hydrophilic residue ratio

71.43%^c

Peptide calculator

Peptide source & Food-borne protein(s) search

Classification	Animal
Organism/Source	Gouda-type cheese
Precursor protein	β-Casein
Residue position	f(71-77)
Precursor protein(s) search	Source.1: DFBPPR7718 ---- Milk proteins ---- Beta-casein Source.2: DFBPPR8489 ---- Milk proteins ---- Beta-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

DPP IV-inhibitory activity	The peptide PQNIPPL showed very low Dipeptidyl Peptidase IV (EC 3.4.14.5) inhibitory activity with the IC₅₀ value of 1500 μM.
Specific target protein(s)	Specific Target Protein(s): Dipeptidyl peptidase 4

Taste properties & Structure

Bitterness

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

SMILES

N1[C@@]([H])(CCC1)C(=O)N[C@@]([H])(CCC(=O)N)C(=O)N[C@@]([H])(CC(=O)N)C(=O)N[C@@]([H])([C@]([H])(CC)C)C(=O)N1[C@@]([H])(CCC1)C(=O)N1[C@@]([H])(CCC1)C(=O)N[C@@]([H])(CC(C)C)C(=O)O

Preparation method

Mode of preparation	Extracting without enzyme
Enzyme(s)/starter culture	The water-soluble extracts of the gouda-type cheeses were prepared without enzyme.

Stability & Cytotoxicity

Peptide stability

Literature report:	The literature speculate that octapeptide, LPQNIPPL, and its derivative peptides formed by digestive enzymes can be absorbed directly into the bloodstream by certain intestinal transporter systems.
EHP-Tool:	Enzymatic Hydrolysis Prediction Tool (EHP-Tool)

Peptide cytotoxicity

Literature report:	N.D
Prediction:	ToxinPred

Additional information

N.D

Database cross-references

[D1]

[D2]

[D3]

[D4]

Reference(s)

Primary literature	Uenishi, H., Kabuki, T., Seto, Y., Serizawa, A., Nakajima, H. Isolation and identification of casein-derived dipeptidyl-peptidase 4 (DPP-4)-inhibitory peptide LPQNIPPL from gouda-type cheese and its effect on plasma glucose in rats. International Dairy Journal. 2012, 22, 24-30. DOI: 10.1016/j.idairyj.2011.08.002
Other literature(s)	N.D
PubDate	2012