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 - DFBPHYCP0001(Hypocholesterolemic peptide)

DFBP ID	DFBPHYCP0001
Peptide sequence	IIAEK
Type	Native peptide
Peptide/Function name	Hypocholesterolemic peptide, Lactostatin

Function-activity relationship

Main bioactivity	Hypocholesterolemic activity
Otheir bioactivity	ACE-inhibitory activity ^[D1], Antioxidative activity ^[D2], DPP IV-inhibitory activity ^[D3], Multifunctional activity ^[D4]

Calculated physicochemical properties

Three-letter amino acid

Ile-Ile-Ala-Glu-Lys

Single-letter amino acid

IIAEK

Peptide length

Peptide mass

Experimental mass	Theoretical mass
N.D	572.69 Da ^c

Net charge

0.00 ^c

Isoelectric point (pI)

6.92 ^c

IC₅₀

N.D

pIC₅₀

N.D

GRAVY

0.6800^c

Hydrophilic residue ratio

60%^c

Peptide calculator

Peptide source & Food-borne protein(s) search

Classification	Animal
Organism/Source	Bovine milk protein
Precursor protein	β-Lactoglobulin
Residue position	f(71-75)
Precursor protein(s) search	Source.1: DFBPPR0115 ---- Milk proteins ---- Beta-lactoglobulin Source.2: DFBPPR2893 ---- Plant proteins ---- Long chain base biosynthesis protein 1c Source.3: DFBPPR3507 ---- Plant proteins ---- Coronatine-insensitive protein homolog 2 Source.4: DFBPPR4999 ---- Plant proteins ---- Leghemoglobin reductase Source.5: DFBPPR6217 ---- Plant proteins ---- Dihydrolipoyl dehydrogenase, mitochondrial Source.6: DFBPPR7687 ---- Milk proteins ---- Beta-lactoglobulin Source.7: DFBPPR7698 ---- Milk proteins ---- Beta-lactoglobulin-1/B Source.8: DFBPPR7714 ---- Milk proteins ---- Beta-lactoglobulin Source.9: DFBPPR8499 ---- Milk proteins ---- Beta-lactoglobulin Source.10: DFBPPR14940 ---- Microorganism protein ---- CCR4-Not complex 3'-5'-exoribonuclease subunit Ccr4
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

Hypocholesterolemic activity

The present study provides the first direct evidence that a new hypocholesterolemic peptide IIAEK derived from β-lactoglobuline can powerfully influence serum cholesterol levels and exhibit a greater hypocholesterolemic activity in comparison with that of medicine, β-sitosterol, in animal studies.
By screening using Caco-2 cells and animal studies, the serum and liver cholesterol levels were significantly lower in rats fed β-lactoglobuline tryptic hydrolysate (LTH) than in those fed casein tryptic hydrolysate (CTH).
The inhibition of micellar solubility of cholesterol which causes the suppression of cholesterol absorption by a direct interaction between cholesterol mixed micelles, and LTH in the jejunal epithelia is part of the mechanism underlying the hypocholesterolemic action of LTH.

Table 1. Effects of Oral Administration of Casein Tryptic Hydrolysate (CTH), β-Lactoglobulin Tryptic Hydrolysate (LTH), β-Sitosterol, or IIAEK on Body and Liver Weights, Food Intake, Serum HDL, and LDL + VLDL-cholesterol in Rats ¹
	Group
	CTH	LTH	β-sitosterol	IIAEK
Body weight gain (g/4 days)	10.4 ± 0.4 ^a	10.5 ± 0.7 ^a	9.5 ± 0.8 ^a	8.7 ± 0.4 ^a
Liver weight (g/100 g body weight)	5.22 ± 0.07 ^b	5.37 ± 0.05 ^{a, b}	5.17 ± 0.10 ^b	5.54 ± 0.11 ^a
Food intake (day 3, g/day)	8.5 ± 0.2 ^a	8.7 ± 0.2 ^a	8.3 ± 0.3 ^a	8.4 ± 0.3 ^a
Serum (mg/dl)
Total cholesterol (a)	529.3 ± 14.4 ^a	441.3 ± 12.0 ^b	435.4 ± 12.8 ^b	328.7 ± 11.3 ^c
HDL cholesterol (b)	42.6 ± 1.6 ^b	50.5 ± 2.4 ^a	52.1 ± 1.7 ^a	47.5 ± 0.8 ^{a, b}
LDL + VLDL-cholesterol ²	486.7 ± 26.7 ^a	390.8 ± 22.9 ^b	383.3 ± 24.2 ^b	281.2 ± 20.6 ^c
Atherogenic Index (b)/(a)	0.08 ± 0.01 ^c	0.11 ± 0.01 ^b	0.12 ± 0.01 ^b	0.15 ± 0.01 ^a
¹ The data are means ± SEM (n = 7). Within a row, means with different superscript letters are significantly different (P < 0.05) by Duncan’s multiple range test. ² Values were calculated as follows: LDL ± VLDL cholesterol = Total cholesterol — HDL cholesterol.

FIG 1. Effects of fractionated peptides derived from β-lactoglobulin on cholesterol absorption in Caco-2 cells in vitro.

Specific target protein(s)

N.D

Taste properties & Structure

Bitterness

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

SMILES

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

Preparation method

Mode of preparation	Enzymatic hydrolysis
Enzyme(s)/starter culture	β-Lactoglobulin was hydrolyzed by porcine trypsin (Novo Industry, Bagsvaerd, Denmark) at pH 8.0 and 37℃ for 3 h.

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

This finding of such a novel hypocholesterolemic peptide should play a crucial role in clarifying the mechanisms by which dietary protein induces differential effects on the serum cholesterol level as well as in developing a functional food or an anti-atherogenic drug.
The researchers successfully developed a transgenic rice accumulating a much higher level of lactostatin by inserting 29 IIAEK sequences into the structurally flexible (nonconserved) regions of soybean seed storage protein, A1aB1b, and introducing it into LGC-1 (low glutelin content mutant 1) as host variety ^[2].

Database cross-references

DFBP

[D1]	DFBPACEI0646
[D2]	DFBPANOX0695
[D3]	DFBPDPIV0212
[D4]	DFBPMUFU0444

[D5]

[D6]

[D7]

[D8]

Reference(s)

Primary literature	Nagaoka S, Futamura Y, Miwa K, Awano T, Yamauchi K, Kanamaru Y, Tadashi K, Kuwata T. Identification of novel hypocholesterolemic peptides derived from bovine milk beta-lactoglobulin. Biochem Biophys Res Commun. 2001 Feb 16;281(1):11-7. PMID: 11178953 DOI: 10.1006/bbrc.2001.4298
Other literature(s)	[1] Wakasa, Yuhya, Tamakoshi, Chiharu, Ohno, Tomoki, et al. The Hypocholesterolemic Activity of Transgenic Rice Seed Accumulating Lactostatin, a Bioactive Peptide Derived from Bovine Milk β-Lactoglobulin[J]. Journal of Agricultural & Food Chemistry, 2011, 59(8):3845-3850. [2] Cabanos, Cerrone, Ekyo, Atsushi, Amari, Yoshiki, et al. High-level production of lactostatin, a hypocholesterolemic peptide, in transgenic rice using soybean A1aB1b as carrier[J]. Transgenic Research, 2013, 22(3):621-629.
PubDate	2001