Peptide name : PTP1

Source/Organism : Skin of a Korean frog, Wrinkled frog

Linear/Cyclic : Cyclic(C15-C21)

Chirality : L

Peptide length: 21

C-terminal modification: Cyclic(C15-C21)

N-terminal modification : Free

Non-natural peptide information: None

Assay type : MTT/MTS assay

Assay time : 96h

Activity : IC50 : >100 µg/ml

Cell line : Hep3B

Cancer type : Liver cancer

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 2252.7799 Dalton

Aliphatic index : 1.442

Instability index : 7.4952

Hydrophobicity (GRAVY) : 1.2286

Isoelectric point : 8.8594

Charge (pH 7) : 1.7373

Aromaticity : 0.095

Molar extinction coefficient (cysteine, cystine): (1490, 1615)

Hydrophobic/hydrophilic ratio : 2.5

hydrophobic moment : -0.878

Missing amino acid : R,W,H,Q,M,E,D,V

Most occurring amino acid : L

Most occurring amino acid frequency : 4

Least occurring amino acid : G

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.4, 0.1, 0.4)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](CCCCN)NC(=O)[C@H](CS)NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](C)NC(=O)[C@H](C)NC(=O)[C@H](CC(C)C)NC(=O)CNC(=O)[C@H](C)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H](N)CC(C)C)[C@@H](C)O)[C@@H](C)CC)[C@@H](C)CC)C(=O)N[C@@H](CO)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CS)C(=O)O

1 : Kim S, et al. In vitro activities of native and designed peptide antibiotics against drug sensitive and resistant tumor cell lines. Peptides. 2003; 24:945-53. doi: 10.1016/s0196-9781(03)00194-3

Paper title : In vitro activities of native and designed peptide antibiotics against drug sensitive and resistant tumor cell lines.

Doi : https://doi.org/10.1016/s0196-9781(03)00194-3

Abstract : In order to develop peptide agents with reduced length and enhanced tumoricidal activity, we have designed gaegurin 6 (GGN6) derivatives through deletions and/or substitutions of amino acids. The deletion of hydrophobic amino terminal region completely abolished antitumor activity whereas the deletion of carboxy terminal region had little influence on antitumor activity. Antitumor activity of the PTP peptides did not correlate with antibacterial activity. PTP7, the most potent derivative, was found to have comparable antitumor activity to GGN6 in spite of reduced number of amino acids which is about half the size of gaegurin 6; furthermore, it showed little cytotoxicity on PBMCs and RBCs. GGN6 and PTP7 also showed equivalent cytotoxicity against drug sensitive (MCF-7) and multidrug-resistant cell lines (MCF-7/DOX). Plasma membrane blebbing and DNA fragmentation of peptide-treated tumor cells indicated that the peptides could induce apoptosis in tumor cells. These results suggest that GGN6 and its derivatives can be developed as new anticancer agents and may provide a new strategy for overcoming MDR which is a major problem in cancer therapy.