Peptide name : N29D

Source/Organism : Synthetic peptide

Linear/Cyclic : Linear

Chirality : L

Peptide length: 30

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : Cell viability assay

Assay time : 24h

Activity : 100% cell viability at 5 µM

Cell line : U-937

Cancer type : Lymphoma cancer

Other activity : Anti-micobial activity

Amino acid composition bar chart :

Molecular mass : 3400.887 Dalton

Aliphatic index : 0.813

Instability index : 61.0167

Hydrophobicity (GRAVY) : -0.94

Isoelectric point : 9.3391

Charge (pH 7) : 2.9409

Aromaticity : 0

Molar extinction coefficient (cysteine, cystine): (0, 125)

Hydrophobic/hydrophilic ratio : 0.66666666

hydrophobic moment : -0.733

Missing amino acid : W,H,M,F,Y

Most occurring amino acid : K

Most occurring amino acid frequency : 4

Least occurring amino acid : P

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.3, 0.3, 0.2)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](C)NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CC(=O)O)NC(=O)[C@@H]1CCCN1)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CCCCN)C(=O)N[C@H](C(=O)N[C@@H](CS)C(=O)N[C@@H](CO)C(=O)N[C@H](C(=O)NCC(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CO)C(=O)N[C@H](C(=O)N[C@@H](CS)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)O)[C@@H](C)CC)[C@@H](C)O)C(C)C

1 : Lee MO, et al. Effects of a single nucleotide polymorphism in the chicken NK-lysin gene on antimicrobial activity and cytotoxicity of cancer cells. Proc Natl Acad Sci U S A. 2012; 109:12087-92. doi: 10.1073/pnas.1209161109

Paper title : Effects of a single nucleotide polymorphism in the chicken NK-lysin gene on antimicrobial activity and cytotoxicity of cancer cells.

Doi : https://doi.org/10.1073/pnas.1209161109

Abstract : NK-lysin is an effector protein of the innate immune system and an important component of host protection. We isolated a SNP in the NK-lysin coding sequence among different chicken breeds. This A to G substitution at the position 271 nucleotide in the ORF results in an Asn (N) to Asp (D) amino acid alteration. We synthesized two 30-aa peptides (N29N and N29D) to compare the biological activity of the helix 2-loop-helix 3 region of NK-lysin resulting from the polymorphic gene. Both peptides were found to be cytotoxic in bacteria and tumor cell cultures at micromolar concentrations. The N29N peptide, however, exhibited greater antibacterial and anticancer activity than the N29D peptide. Circular dichroism spectroscopy of the two peptides in negatively charged single unilamellar vesicles showed spectra typical of α-helical peptides. The helical profile of N29D was reduced substantially compared with that of N29N. However, no structural change was observed in neutral vesicles. ζ-Potential measurements of liposomes incubated with increasing peptide concentrations allowed surface charge neutralization with a negatively charged lipid, but not with a zwitterionic lipid. This result suggests that a difference in electrostatic interaction between lipid membranes and the helical peptides results from the polymorphic gene and is subsequently an important factor in cell lytic activity of variant NK-lysin peptides.