Peptide name : Caerin 1.7

Source/Organism : Orange thighed treefrog, Australia

Linear/Cyclic : Not found

Chirality : L

Peptide length: 24

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 : Anti-microbial activity

Amino acid composition bar chart :

Molecular mass : 2524.0546 Dalton

Aliphatic index : 1.420

Instability index : 23.8583

Hydrophobicity (GRAVY) : 0.7625

Isoelectric point : 9.7033

Charge (pH 7) : 1.9343

Aromaticity : 0.041

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

Hydrophobic/hydrophilic ratio : 2.42857142

hydrophobic moment : -1.162

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

Most occurring amino acid : L

Most occurring amino acid frequency : 4

Least occurring amino acid : F

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.4, 0.2, 0.4)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@@H](NC(=O)[C@@H]1CCCN1C(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CC(C)C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CCCCN)NC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](CO)NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(C)C)NC(=O)CN)C(C)C)C(C)C)C(C)C)C(C)C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCC(=O)O)C(=O)N[C@@H](CCCCN)C(=O)O

1 : Steinborner ST, et al. New caerin antibacterial peptides from the skin glands of the Australian tree frog Litoria xanthomera. J Pept Sci. 1997; 3:181-5. doi: 10.1002/(sici)1099-1387(199705)3:3<181::aid-psc97>3.0.co;2-k

2 : Wang G, et al. APD2: the updated antimicrobial peptide database and its application in peptide design. Nucleic Acids Res. 2009; 37:D933-7. doi: 10.1093/nar/gkn823

Paper title : New caerin antibacterial peptides from the skin glands of the Australian tree frog Litoria xanthomera.

Doi : https://doi.org/10.1002/(sici)1099-1387(199705)3:3<181::aid-psc97>3.0.co;2-k

Abstract : The secretion of the skin glands of the 'orange-thighed frog' Litoria xanthomera contains seven peptides. One of these is the know hypotensive peptide caerulein. Two new peptides, caerin 1.6 [GLFSVLGAVAKHVLPHVVPVIAEKL(NH2)], and caerin 1.7 [GLFKVLGSVAKHLLPHVAPVIAEKL(NH2)] show antibacterial properties. Two other peptides lack the first two amino acid residues of caerins 1.6 and 1.7 and show no antibacterial activity. The identification of the peptides in Litoria xanthomera confirms that this species is related to Litoria caerula, Litoria gilleni and Litoria splendida but not as closely as those three species are related to each other.

Paper title : APD2: the updated antimicrobial peptide database and its application in peptide design.

Doi : https://doi.org/10.1093/nar/gkn823

Abstract : The antimicrobial peptide database (APD, http://aps.unmc.edu/AP/main.php) has been updated and expanded. It now hosts 1228 entries with 65 anticancer, 76 antiviral (53 anti-HIV), 327 antifungal and 944 antibacterial peptides. The second version of our database (APD2) allows users to search peptide families (e.g. bacteriocins, cyclotides, or defensins), peptide sources (e.g. fish, frogs or chicken), post-translationally modified peptides (e.g. amidation, oxidation, lipidation, glycosylation or d-amino acids), and peptide binding targets (e.g. membranes, proteins, DNA/RNA, LPS or sugars). Statistical analyses reveal that the frequently used amino acid residues (>10%) are Ala and Gly in bacterial peptides, Cys and Gly in plant peptides, Ala, Gly and Lys in insect peptides, and Leu, Ala, Gly and Lys in amphibian peptides. Using frequently occurring residues, we demonstrate database-aided peptide design in different ways. Among the three peptides designed, GLK-19 showed a higher activity against Escherichia coli than human LL-37.