Peptide name : LfcinB

Source/Organism : Bovine lactoferrin (Lf-B)

Linear/Cyclic : Linear

Chirality : L

Peptide length: 12

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : MTT/MTS assay

Assay time : Not found

Activity : IC50 : 40 ± 7 µM

Cell line : FEMX

Cancer type : Skin cancer

Other activity : Anti-microbial activity

Amino acid composition bar chart :

Molecular mass : 1753.151 Dalton

Aliphatic index : 0

Instability index : 92.1083

Hydrophobicity (GRAVY) : -1.941

Isoelectric point : 11.735

Charge (pH 7) : 5.7472

Aromaticity : 0.25

Molar extinction coefficient (cysteine, cystine): (11000, 11000)

Hydrophobic/hydrophilic ratio : 0.71428571

hydrophobic moment : -0.833

Missing amino acid : H,T,P,I,E,S,D,Y,L,N,A,V,G

Most occurring amino acid : K

Most occurring amino acid frequency : 3

Least occurring amino acid : F

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.3, 0, 0.2)

SMILES Notation: CSCC[C@H](NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CS)NC(=O)[C@H](CCCCN)NC(=O)[C@@H](N)Cc1ccccc1)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)O

1 : Fadnes B, et al. The anticancer activity of lytic peptides is inhibited by heparan sulfate on the surface of the tumor cells. BMC Cancer. 2009; 9:183. doi: 10.1186/1471-2407-9-183

2 : Pepe G, et al. Potential anticarcinogenic peptides from bovine milk. J Amino Acids. 2013; 2013:939804. doi: 10.1155/2013/939804

Paper title : The anticancer activity of lytic peptides is inhibited by heparan sulfate on the surface of the tumor cells.

Doi : https://doi.org/10.1186/1471-2407-9-183

Abstract : BACKGROUND: Cationic antimicrobial peptides (CAPs) with antitumor activity constitute a promising group of novel anticancer agents. These peptides induce lysis of cancer cells through interactions with the plasma membrane. It is not known which cancer cell membrane components influence their susceptibility to CAPs. We have previously shown that CAPs interact with the two glycosaminoglycans (GAGs), heparan sulfate (HS) and chondroitin sulfate (CS), which are present on the surface of most cells. The purpose of this study was to investigate the role of the two GAGs in the cytotoxic activity of CAPs. METHODS: Various cell lines, expressing different levels of cell surface GAGs, were exposed to bovine lactoferricin (LfcinB) and the designer peptide, KW5. The cytotoxic effect of the peptides was investigated by use of the colorimetric MTT viability assay. The cytotoxic effect on wild type CHO cells, expressing normal amounts of GAGs on the cell surface, and the mutant pgsA-745, that has no expression of GAGs on the cell surface, was also investigated. RESULTS: We show that cells not expressing HS were more susceptible to CAPs than cells expressing HS at the cell surface. Further, exogenously added heparin inhibited the cytotoxic effect of the peptides. Chondroitin sulfate had no effect on the cytotoxic activity of KW5 and only minor effects on LfcinB cytotoxicity. CONCLUSION: Our results show for the first time that negatively charged molecules at the surface of cancer cells inhibit the cytotoxic activity of CAPs. Our results indicate that HS at the surface of cancer cells sequesters CAPs away from the phospholipid bilayer and thereby impede their ability to induce cytolysis.

Paper title : Potential anticarcinogenic peptides from bovine milk.

Doi : https://doi.org/10.1155/2013/939804

Abstract : BOVINE MILK POSSESSES A PROTEIN SYSTEM CONSTITUTED BY TWO MAJOR FAMILIES OF PROTEINS: caseins (insoluble) and whey proteins (soluble). Caseins ( α S1, α S2, β , and κ ) are the predominant phosphoproteins in the milk of ruminants, accounting for about 80% of total protein, while the whey proteins, representing approximately 20% of milk protein fraction, include β -lactoglobulin, α -lactalbumin, immunoglobulins, bovine serum albumin, bovine lactoferrin, and lactoperoxidase, together with other minor components. Different bioactivities have been associated with these proteins. In many cases, caseins and whey proteins act as precursors of bioactive peptides that are released, in the body, by enzymatic proteolysis during gastrointestinal digestion or during food processing. The biologically active peptides are of particular interest in food science and nutrition because they have been shown to play physiological roles, including opioid-like features, as well as immunomodulant, antihypertensive, antimicrobial, antiviral, and antioxidant activities. In recent years, research has focused its attention on the ability of these molecules to provide a prevention against the development of cancer. This paper presents an overview of antitumor activity of caseins and whey proteins and derived peptides.