Peptide name : Dermaseptin-PS1

Source/Organism : Skin, the waxy monkey tree frog, South America

Linear/Cyclic : Not found

Chirality : Not found

Peptide length: 31

C-terminal modification: Not found

N-terminal modification : Free

Non-natural peptide information: None

Assay type : Not specified

Assay time : Not found

Activity : Not found

Cell line : Not found

Cancer type : Not found

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 3164.7621 Dalton

Aliphatic index : 1.167

Instability index : 2.2484

Hydrophobicity (GRAVY) : 0.5032

Isoelectric point : 10.001

Charge (pH 7) : 2.8802

Aromaticity : 0.032

Molar extinction coefficient (cysteine, cystine): (5500, 5500)

Hydrophobic/hydrophilic ratio : 1.81818181

hydrophobic moment : -0.669

Missing amino acid : C,R,P,E,F,Y,N

Most occurring amino acid : A

Most occurring amino acid frequency : 7

Least occurring amino acid : W

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.5, 0.1, 0.3)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@@H](NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](C)NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@H](C)NC(=O)[C@H](C)NC(=O)[C@H](CCCCN)NC(=O)CNC(=O)[C@H](C)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCSC)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@H](Cc1c[nH]c2ccccc12)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](C)N)[C@@H](C)O)[C@@H](C)O)C(C)C)C(C)C)[C@@H](C)O)C(=O)N[C@@H](CO)C(=O)N[C@@H](CCC(N)=O)C(=O)O

1 : Wu Z, et al. Skin-Derived SPINK9 Kills Escherichia coli. J Invest Dermatol. 2019; 139:1135-1142. doi: 10.1016/j.jid.2018.11.004

Paper title : Skin-Derived SPINK9 Kills Escherichia coli.

Doi : https://doi.org/10.1016/j.jid.2018.11.004

Abstract : Antimicrobial peptides play a critical role in the barrier function of human skin. They offer a fast response to invading microorganisms and protect from external microbial infection. Here we show the isolation of the kallikrein-related peptidase inhibitor SPINK9 as a major antibacterial factor from healthy stratum corneum. In total, six N-terminal SPINK9 variants were identified in the stratum corneum. Whereas all variants exhibited similar inhibition activities against kallikrein-related peptidase, only three variants with either lysine or glutamine as their first N-terminal residues were able to kill various Escherichia coli strains, but not other bacteria or fungi. The killing activity also depended on the sequence essential for kallikrein-related peptidase inhibition. Ultrastructural electron microscopy analyses suggested that SPINK9 entered the cell and killed growing bacteria. A bacterial chaperone, SKP, was identified as the major SPINK9 interacting partner in E. coli cells. The Skp-deleted mutant was more sensitive to SPINK9 than the wild-type control, suggesting that the bactericidal activity of SPINK9 should first overcome the resistance from the bacterial chaperone SKP. Thus, SPINK9 is a member of epidermal antimicrobial peptides for selective killing of E. coli, which might contribute to the innate barrier function of human skin.