Peptide name : Aurein-3.1 [Cleaved into: Aurein-3.1.1; Aurein-3.1.2]

Source/Organism : Green and golden bell frog

Linear/Cyclic : Linear

Chirality : Not found

Peptide length: 70

C-terminal modification: Linear

N-terminal modification : Amidation

Non-natural peptide information: None

Assay type : Not specified

Assay time : Not found

Activity : LC50 : 10-5 - 10-4 M

Cell line : Human tumour cell lines

Cancer type : Lung cancer

Other activity : Anti-bacterial activity

Amino acid composition bar chart :

Molecular mass : 7874.9146 Dalton

Aliphatic index : 0.92

Instability index : 52.1329

Hydrophobicity (GRAVY) : -0.49

Isoelectric point : 5.6699

Charge (pH 7) : -2.3099

Aromaticity : 0.057

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

Hydrophobic/hydrophilic ratio : 0.89189189

hydrophobic moment : 0.3604

Missing amino acid : T,W,P,Y

Most occurring amino acid : E

Most occurring amino acid frequency : 11

Least occurring amino acid : M

Least occurring amino acid frequency : 1

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

SMILES Notation: CC[C@H](C)[C@H](NC(=O)[C@H](CO)NC(=O)CNC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)CNC(=O)[C@H](C)NC(=O)[C@@H](NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@@H](NC(=O)[C@@H](NC(=O)[C@H](CC(=O)O)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(C)C)NC(=O)CNC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CO)NC(=O)CNC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](Cc1c[nH]cn1)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](C)NC(=O)[C@H](C)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCC(=O)O)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](CCC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CC(N)=O)NC(=O)[C@H](CCC(N)=O)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCC(=O)O)NC(=O)[C@H](CS)NC(=O)[C@@H](NC(=O)[C@H](CO)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@@H](NC(=O)[C@H](CC(C)C)NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(C)C)NC(=O)[C@@H](NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CO)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CCCCN)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](Cc1ccccc1)NC(=O)[C@H](C)NC(=O)[C@@H](N)CCSC)C(C)C)C(C)C)[C@@H](C)CC)[C@@H](C)CC)C(C)C)[C@@H](C)CC)[C@@H](C)CC)C(=O)NCC(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CCCNC(=N)N)C(=O)O

1 : Chen T, et al. The structural organization of aurein precursor cDNAs from the skin secretion of the Australian green and golden bell frog, Litoria aurea. Regul Pept. 2005; 128:75-83. doi: 10.1016/j.regpep.2004.12.022

2 : Rozek T, et al. The antibiotic and anticancer active aurein peptides from the Australian Bell Frogs Litoria aurea and Litoria raniformis the solution structure of aurein 1.2. Eur J Biochem. 2000; 267:5330-41. doi: 10.1046/j.1432-1327.2000.01536.x

Paper title : The structural organization of aurein precursor cDNAs from the skin secretion of the Australian green and golden bell frog, Litoria aurea.

Doi : https://doi.org/10.1016/j.regpep.2004.12.022

Abstract : Aureins are a family of peptides (13-25 residues), some of which possess potent antimicrobial and anti-cancer properties, which have been classified into 5 subgroups based upon primary structural similarities. They were originally isolated from the defensive skin secretions of the closely related Australian bell frogs, Litoria aurea and Litoria raniformis, and of the 23 aurein peptides identified, 10 are common to both species. Using a recently developed technique, we have constructed a cDNA library from the defensive secretion of the green and golden bell frog, L. aurea, and successfully cloned a range of aurein precursor transcripts containing entire open-reading frames. All open-reading frames consisted of a putative signal peptide and an acidic pro-region followed by a single copy of aurein. The deduced precursor structures for the most active aureins (2.2 and 3.1) confirmed the presence of a C-terminal amidation motif whereas that of aurein 5.3 did not. Processed peptides corresponding in molecular mass to aureins 2.2, 2.3, 2.5, 3.1 and 5.3 were identified in the same secretion sample using LC/MS. The application of this technique thus permits parallel peptidomic and transcriptomic analyses on the same lyophilized skin secretion sample circumventing sacrifice of specimens of endangered herpetofauna.

Paper title : The antibiotic and anticancer active aurein peptides from the Australian Bell Frogs Litoria aurea and Litoria raniformis the solution structure of aurein 1.2.

Doi : https://doi.org/10.1046/j.1432-1327.2000.01536.x

Abstract : Seventeen aurein peptides are present in the secretion from the granular dorsal glands of the Green and Golden Bell Frog Litoria aurea, and 16 from the corresponding secretion of the related Southern Bell Frog L. raniformis. Ten of these peptides are common to both species. Thirteen of the aurein peptides show wide-spectrum antibiotic and anticancer activity. These peptides are named in three groups (aureins 1-3) according to their sequences. Amongst the more active peptides are aurein 1.2 (GLFDIIKKIAESF-NH2), aurein 2.2 (GLFDIVKKVVGALGSL-NH2) and aurein 3.1 (GLFDIVKKIAGHIAGSI-NH2). Both L. aurea and L. raniformis have endoproteases that deactivate the major membrane-active aurein peptides by removing residues from both the N- and C-termini of the peptides. The most abundant degradation products have two residues missing from the N-terminal end of the peptide. The solution structure of the basic peptide, aurein 1.2, has been determined by NMR spectroscopy to be an amphipathic alpha-helix with well-defined hydrophilic and hydrophobic regions. Certain of the aurein peptides (e.g. aureins 1.2 and 3.1) show anticancer activity in the NCI test regime, with LC50 values in the 10-5-10-4 M range. The aurein 1 peptides have only 13 amino-acid residues: these are the smallest antibiotic and anticancer active peptides yet reported from an anuran. The longer aurein 4 and 5 peptides, e.g. aurein 4.1 (GLIQTIKEKLKELAGGLVTGIQS-OH) and aurein 5. 1 (GLLDIVTGLLGNLIVDVLKPKTPAS-OH) show neither antibacterial nor anticancer activity.