Peptide name : Maximin 4

Source/Organism : Yunnan firebelly toad

Linear/Cyclic : Not found

Chirality : L

Peptide length: 27

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; Spermicidal action; Anti-HIV activity

Amino acid composition bar chart :

Molecular mass : 2613.1031 Dalton

Aliphatic index : 1.303

Instability index : 7.2481

Hydrophobicity (GRAVY) : 0.5926

Isoelectric point : 9.8256

Charge (pH 7) : 2.7579

Aromaticity : 0.037

Molar extinction coefficient (cysteine, cystine): (1490, 1490)

Hydrophobic/hydrophilic ratio : 2.375

hydrophobic moment : -0.658

Missing amino acid : C,R,W,H,Q,T,P,M,F,D

Most occurring amino acid : A

Most occurring amino acid frequency : 6

Least occurring amino acid : I

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.5, 0.2, 0.3)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)CN)C(=O)NCC(=O)NCC(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CO)C(=O)N[C@@H](C)C(=O)NCC(=O)N[C@@H](CCCCN)C(=O)N[C@@H](C)C(=O)N[C@@H](C)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCCCN)C(=O)NCC(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCCCN)C(=O)N[C@H](C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](C)C(=O)N[C@@H](CCC(=O)O)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](Cc1ccc(O)cc1)C(=O)N[C@@H](C)C(=O)N[C@@H](CC(N)=O)C(=O)O)C(C)C)C(C)C

1 : 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

2 : Lai R, et al. Antimicrobial peptides from skin secretions of Chinese red belly toad Bombina maxima. Peptides. 2002; 23:427-35. doi: 10.1016/s0196-9781(01)00641-6

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.

Paper title : Antimicrobial peptides from skin secretions of Chinese red belly toad Bombina maxima.

Doi : https://doi.org/10.1016/s0196-9781(01)00641-6

Abstract : Two groups of antimicrobial peptides have been isolated from skin secretions of Bombina maxima. Peptides in the first group, named maximins 1, 2, 3, 4 and 5, are structurally related to bombinin-like peptides (BLPs). Unlike BLPs, sequence variations in maximins occurred all through the molecules. In addition to the potent antimicrobial activity, cytotoxicity against tumor cells and spermicidal action of maximins, maximin 3 possessed a significant anti-HIV activity. Maximins 1 and 3 were toxic to mice with LD(50) values of 8.2 and 4.3 mg/kg, respectively. Peptides in the second group, termed maximins H1, H2, H3 and H4, are homologous with bombinin H peptides. cDNA sequences revealed that one maximin peptide plus one maximin H peptide derived from a common larger protein.