Peptide name : Phylloseptin-PTa

Source/Organism : Skin secretions, the Brown-bellied Leaf Frog, South America

Linear/Cyclic : Not found

Chirality : Not found

Peptide length: 19

C-terminal modification: Not found

N-terminal modification : Amidation

Non-natural peptide information: None

Assay type : MTT Cell viability assay

Assay time : 24h

Activity : IC50 : 6.73 μM

Cell line : NCI-H157

Cancer type : Lung cancer

Other activity : Anti-microbial activity

Amino acid composition bar chart :

Molecular mass : 1933.3829 Dalton

Aliphatic index : 1.647

Instability index : 5.5158

Hydrophobicity (GRAVY) : 1.2895

Isoelectric point : 10.002

Charge (pH 7) : 1.8453

Aromaticity : 0.052

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

Hydrophobic/hydrophilic ratio : 3.75

hydrophobic moment : 1.5825

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

Most occurring amino acid : L

Most occurring amino acid frequency : 4

Least occurring amino acid : F

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.5, 0.2, 0.4)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)CNC(=O)CNC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@@H]1CCCN1C(=O)[C@@H](NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H](N)Cc1ccccc1)[C@@H](C)CC)[C@@H](C)CC)C(=O)N[C@@H](C)C(=O)N[C@@H](C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CC(C)C)C(=O)O

1 : Liu J, et al. Discovery of Phylloseptins that Defense against Gram-Positive Bacteria and Inhibit the Proliferation of the Non-Small Cell Lung Cancer Cell Line, from the Skin Secretions of Phyllomedusa Frogs. Molecules. 2017; 22:(unknown pages). doi: 10.3390/molecules22091428

Paper title : Discovery of Phylloseptins that Defense against Gram-Positive Bacteria and Inhibit the Proliferation of the Non-Small Cell Lung Cancer Cell Line, from the Skin Secretions of Phyllomedusa Frogs.

Doi : https://doi.org/10.3390/molecules22091428

Abstract : The growing occurrence of bacterial resistance to conventional antibiotics has called for the development of new classes of antimicrobial agents. Antimicrobial peptides (AMPs) with broad antimicrobial spectrum derived from frog skin secretions have been demonstrated to be promising candidates for new antibiotic development. A proven rich source of these compounds are the skin secretions of the frogs in the Phyllomedusa genus. In this study, two novel phylloseptin peptides-phylloseptin-PTa and phylloseptin-PHa-were isolated from the skin secretions of the South American frogs, Phyllomedusa tarsius (P. tarsius) and Phyllomedusa hypochondrialis (P. hypochondrialis) through parallel transcriptomic and peptidomic studies. Replicates obtained by chemical synthesis were structurally analysed and shown to adopt an α-helix configuration in an amphiphilic environment. Both peptides demonstrated antimicrobial activities against planktonic Gram-positive bacteria strains, including Staphylococcus aureus, Enterococcus faecalis and methicillin-resistant Staphylococcus aureus , biofilms, as well as cytostatic effects on the non-small cell lung cancer cell line, NCI-H157, with relatively low haemolysis on horse erythrocytes and low cytotoxicity on the human microvascular endothelial cell line, HMEC-1. The discovery of phylloseptin peptides may further inspire the development of new types of antibiotics.