Peptide name : Temporin-PKE-i

Source/Organism : Synthetic

Linear/Cyclic : Linear

Chirality : Mix

Peptide length: 17

C-terminal modification: Linear

N-terminal modification : Amidation

Non-natural peptide information:

Assay type : MTT assay

Assay time : 24-h

Activity : IC50 = 4.46 μM

Cell line : U251-MG

Cancer type : Brain Tumor

Other activity : Antimicrobial

Amino acid composition bar chart :

Molecular mass : 1842.3102 Dalton

Aliphatic index : 1.664

Instability index : 33.4118

Hydrophobicity (GRAVY) : 1.8118

Isoelectric point : 8.7501

Charge (pH 7) : 0.7591

Aromaticity : 11.76

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

Hydrophobic/hydrophilic ratio : 4.3333

hydrophobic moment : 0.3549

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

Most occurring amino acid : L

Most occurring amino acid frequency : 5

Least occurring amino acid : G

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (41., 29., 58.)

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

1 : Lin Y, et al. Discovery of a Novel Antimicrobial Peptide, Temporin-PKE, from the Skin Secretion of Pelophylax kl. esculentus, and Evaluation of Its Structure-Activity Relationships. Biomolecules. 2022; 12:(unknown pages). doi: 10.3390/biom12060759

Paper title : Discovery of a Novel Antimicrobial Peptide, Temporin-PKE, from the Skin Secretion of Pelophylax kl. esculentus, and Evaluation of Its Structure-Activity Relationships.

Doi : https://doi.org/10.3390/biom12060759

Abstract : Bacterial resistance against antibiotics has led to increasing numbers of treatment failures, and AMPs are widely accepted as becoming potential alternatives due to their advantages. Temporin-PKE is a novel peptide extracted from the skin secretion of Pelophylax kl. esculentus and it displays a strong activity against Gram-positive bacteria, with an extreme cytotoxicity. Incorporating positively charged residues and introducing D-amino acids were the two main strategies adopted for the modifications. The transformation of the chirality of Ile could reduce haemolytic activity, and an analogue with appropriate D-isoforms could maintain antimicrobial activity and stability. The substitution of hydrophobic residues could bring about more potent and broad-spectrum antimicrobial activities. The analogues with Lys were less harmful to the normal cells and their stabilities remained at similarly high levels compared to temporin-PKE. The optimal number of charges was three, and the replacement on the polar face was a better choice. Temporin-PKE-3K exerted dually efficient functions includingstrong antimicrobial and anticancer activity. This analogue showed a reduced possibility for inducing resistance in MRSA and Klebsiella pneumoniae, a rather strong antimicrobial activity in vivo, and it exhibited the highest therapeutic index such that temporin-PKE-3K has the potential to be developed as a clinical drug.