Peptide name : TP3

Source/Organism : Nile tilapia

Linear/Cyclic : Linear

Chirality : Not found

Peptide length: 23

C-terminal modification: Linear

N-terminal modification : Amidation

Non-natural peptide information: None

Assay type : In vitro cytotoxicity assay

Assay time : 24h

Activity : MIC : > 100 µg/ml

Cell line : Tilapia ovary (TO2) cells

Cancer type : Ovarian cancer

Other activity : Anti-microbial activity

Amino acid composition bar chart :

Molecular mass : 2556.965 Dalton

Aliphatic index : 1.313

Instability index : 57.3435

Hydrophobicity (GRAVY) : 0.5913

Isoelectric point : 8.79

Charge (pH 7) : 1.2821

Aromaticity : 0.087

Molar extinction coefficient (cysteine, cystine): (0, 0)

Hydrophobic/hydrophilic ratio : 1.55555555

hydrophobic moment : 0.6271

Missing amino acid : C,R,W,Q,T,P,M,E,D,Y,N,A

Most occurring amino acid : H

Most occurring amino acid frequency : 6

Least occurring amino acid : V

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.1, 0.2, 0.4)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@@H](NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CCCCN)NC(=O)CNC(=O)[C@@H](NC(=O)[C@H](CO)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(C)C)NC(=O)CNC(=O)CNC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@@H](NC(=O)[C@@H](N)Cc1ccccc1)[C@@H](C)CC)[C@@H](C)CC)[C@@H](C)CC)C(C)C)[C@@H](C)CC)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)NCC(=O)N[C@@H](Cc1c[nH]cn1)C(=O)O

1 : Peng KC, et al. Five different piscidins from Nile tilapia, Oreochromis niloticus: analysis of their expressions and biological functions. PLoS One. 2012; 7:e50263. doi: 10.1371/journal.pone.0050263

Paper title : Five different piscidins from Nile tilapia, Oreochromis niloticus: analysis of their expressions and biological functions.

Doi : https://doi.org/10.1371/journal.pone.0050263

Abstract : Piscidins are antimicrobial peptides (AMPs) that play important roles in helping fish resist pathogenic infections. Through comparisons of tilapia EST clones, the coding sequences of five piscidin-like AMPs (named TP1∼5) of Nile tilapia, Oreochromis niloticus, were determined. The complete piscidin coding sequences of TP1, -2, -3, -4, and -5 were respectively composed of 207, 234, 231, 270, and 195 bases, and each contained a translated region of 68, 77, 76, 89, and 64 amino acids. The tissue-specific, Vibrio vulnificus stimulation-specific, and Streptococcus agalactiae stimulation-specific expressions of TP2, -3, and -4 mRNA were determined by a comparative RT-PCR. Results of the tissue distribution analysis revealed high expression levels of TP2 mRNA in the skin, head kidneys, liver, and spleen. To study bacterial stimulation, S. agalactiae (SA47) was injected, and the TP4 transcript was upregulated by >13-fold (compared to the wild-type (WT) control, without injection) and was 60-fold upregulated (compared to the WT control, without injection) 24 h after the S. agalactiae (SA47) injection in the spleen and gills. Synthesized TP3 and TP4 peptides showed antimicrobial activities against several bacteria in this study, while the synthesized TP1, -2, and -5 peptides did not. The synthesized TP2, -3, and -4 peptides showed hemolytic activities and synthesized TP3 and TP4 peptides inhibited tilapia ovary cell proliferation with a dose-dependent effect. In summary, the amphiphilic α-helical cationic peptides of TP3 and TP4 may represent novel and potential antimicrobial agents for further peptide drug development.