Peptide name : Pep27anal3

Source/Organism : Pneumococcus

Linear/Cyclic : Linear

Chirality : L

Peptide length: 27

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : MTT/MTS assay

Assay time : 20.08min

Activity : IC50 : 38 µM

Cell line : MCF-7

Cancer type : Breast cancer

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 3347.8055 Dalton

Aliphatic index : 0.614

Instability index : 23.5852

Hydrophobicity (GRAVY) : -0.929

Isoelectric point : 9.992

Charge (pH 7) : 2.5858

Aromaticity : 0.185

Molar extinction coefficient (cysteine, cystine): (17990, 17990)

Hydrophobic/hydrophilic ratio : 0.92857142

hydrophobic moment : 0.598

Missing amino acid : C,T,I,E

Most occurring amino acid : K

Most occurring amino acid frequency : 3

Least occurring amino acid : M

Least occurring amino acid frequency : 1

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

SMILES Notation: CSCC[C@H](N)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](Cc1c[nH]c2ccccc12)C(=O)N[C@@H](Cc1ccccc1)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CO)C(=O)N[C@@H](CO)C(=O)NCC(=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](C)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](Cc1c[nH]c2ccccc12)C(=O)N1CCC[C@H]1C(=O)N[C@@H](C)C(=O)N[C@@H](Cc1c[nH]c2ccccc12)C(=O)N[C@@H](CC(=O)O)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CCCNC(=N)N)C(=O)N[C@@H](CCCCN)C(=O)O)C(C)C

1 : Lee DG, et al. Functional and structural characteristics of anticancer peptide Pep27 analogues. Cancer Cell Int. 2005; 5:21. doi: 10.1186/1475-2867-5-21

Paper title : Functional and structural characteristics of anticancer peptide Pep27 analogues.

Doi : https://doi.org/10.1186/1475-2867-5-21

Abstract : BACKGROUND: A secreted peptide Pep27 initiates the cell death program in S. pneumoniae through signal transduction. This study was undertaken to evaluate the relation between the structure and cytotoxic activity of Pep27 and its analogues on cancer cells. RESULTS: Pep27anal2 characterized substituting (2R-->W), (4E-->W), (11S-->W) and (13Q-->W) in native Pep27, exhibited greater hydrophobicity and anticancer activity than Pep27 and other analogues. The IC50 values of Pep27anal2 were approximately 10 - 30 microM in a number of cell lines (AML-2, HL-60, Jurkat, MCF-7 and SNU-601). Confocal microscopy showed that Pep27anal2-FITC was localized in the plasma membrane, and then moving from the membrane to subcellular compartments with the initiation of membrane blebbing. Flow cytometric analysis using propidium iodide and Annexin V also revealed that Pep27anal2 induced apoptosis with minor membrane damage. Electron microscopy revealed that Pep27 induced apoptosis in Jurkat cells. The anticancer activity of Pep27anal2 was neither abrogated by pan-caspase inhibitor (Z-VAD-fmk) nor related to cytochrome c release from mitochondria. The 3D solution structures of these two Pep27 peptides revealed that both form a random coil conformation in water; however, they adopted stable alpha-helical conformations in solutions. CONCLUSION: The results indicate that Pep27anal2 can penetrate the plasma membrane, and then induce apoptosis in both caspase-and cytochrome c-independent manner. The hydrophobicity of Pep27anal2 appears to play an important role in membrane permeabilization and/or anticancer properties. The structure-functional relationships of these peptides are also discussed. It is proposed that Pep27anal2 is a potential candidate for anticancer therapeutic agents.