Peptide name : Smp24

Source/Organism : Venom, Israeli Gold Scorpion

Linear/Cyclic : Linear

Chirality : Not found

Peptide length: 24

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : ATP release assay

Assay time : 24h

Activity : MIC : 32 μg/ml

Cell line : HepG2

Cancer type : Liver cancer

Other activity : Anti-microbial activity

Amino acid composition bar chart :

Molecular mass : 2578.0557 Dalton

Aliphatic index : 1.058

Instability index : 33.3292

Hydrophobicity (GRAVY) : 0.3125

Isoelectric point : 10.001

Charge (pH 7) : 2.7572

Aromaticity : 0.125

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

Hydrophobic/hydrophilic ratio : 1.66666666

hydrophobic moment : 0.4661

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

Most occurring amino acid : L

Most occurring amino acid frequency : 4

Least occurring amino acid : W

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.4, 0.3, 0.4)

SMILES Notation: CC[C@H](C)[C@H](N)C(=O)N[C@@H](Cc1c[nH]c2ccccc12)C(=O)N[C@@H](CO)C(=O)N[C@@H](Cc1ccccc1)C(=O)N[C@@H](CC(C)C)C(=O)N[C@H](C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](C)C(=O)N[C@@H](C)C(=O)N[C@H](C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(C)C)C(=O)N1CCC[C@H]1C(=O)N[C@@H](CO)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](Cc1ccccc1)C(=O)NCC(=O)NCC(=O)NCC(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](CO)C(=O)O)[C@@H](C)O)[C@@H](C)CC

1 : Harrison PL, et al. Characterisation of three alpha-helical antimicrobial peptides from the venom of Scorpio maurus palmatus. Toxicon. 2016; 117:30-6. doi: 10.1016/j.toxicon.2016.03.014

Paper title : Characterisation of three alpha-helical antimicrobial peptides from the venom of Scorpio maurus palmatus.

Doi : https://doi.org/10.1016/j.toxicon.2016.03.014

Abstract : Scorpion venoms provide a rich source of anti-microbial peptides. Here we characterise three from the venom of Scorpion maurus palmatus. Smp13 is biologically inactive, despite sharing homology with other antimicrobial peptides, probably because it lacks a typically charged structure. Both Smp-24 and Smp-43 have broad spectrum antimicrobial activity, disrupting bacterial membranes. In addition, there is evidence that Smp24 may inhibit DNA synthesis in Bacillus subtilis. Smp24 haemolysed red blood cells but in contrast, Smp43 was non-haemolytic. The introduction of a flexible Gly-Val-Gly hinge into the middle of Smp24 did not alter the haemolytic activity of Smp24 (as might have been predicted from earlier studies with Pandinin2 (Pin2), although C-terminal truncation of Smp-24 reduced its haemolytic activity, in agreement with earlier Pin 2 studies. Smp24 and its derivatives, as well as Smp-43, were all cytotoxic (ATP release assay) toward mammalian HepG2 liver cells. Our results highlight the beneficial effect of helical-hinge-helical conformation on promoting prokaryotic selectivity of long chain scorpion AMPs, as well as the importance of examining a wide range of mammalian cell types in cytotoxicity testing.