An anionic antimicrobial peptide from toad Bombina maxima.
Amphibian skin is a rich resource of antimicrobial peptides like maximins and maximins H from toad Bombina maxima. A novel cDNA clone encoding a precursor protein that comprises maximin 3 and a novel peptide, named maximin H5, was isolated from a skin cDNA library of B. maxima. The predicted primary structure of maximin H5 is ILGPVLGLVSDTLDDVLGIL-NH2. Containing three aspartate residues and no basic amino acid residues, maximin H5 is characterized by an anionic property. Different from cationic maximin H peptides, only Gram-positive strain Staphylococcus aureus was sensitive to maximin H5, while the other bacterial and fungal strains tested were resistant to it. The presence of metal ions, like Zn2+ and Mg2+, did not increase its antimicrobial potency. Maximin H5 represents the first example of potential anionic antimicrobial peptides from amphibians. The results provide the first evidence that, together with cationic antimicrobial peptides, anionic antimicrobial peptides may also exist naturally as part of the innate defense system.
Department of Animal Toxinology, Kunming Institute of Zoology, Chinese Academy of Sciences, 32 East Jiao Chang Road, Kunming, Yunnan, People's Republic of China.
Ren
R
Lai
Hen
H
Liu
Wen
W
Hui Lee
Yun
Y
Zhang
D000595:Amino Acid Sequence; D029845:Amphibian Proteins; D000818:Animals; D000838:Anions; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D000890:Anti-Infective Agents / Q000737:chemistry*; D001001:Anura / Q000378:metabolism*; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004912:Erythrocytes / Q000382:microbiology; D015723:Gene Library; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000235:genetics*; D011506:Proteins / Q000737:chemistry* / Q000235:genetics; D011817:Rabbits; D017386:Sequence Homology, Amino Acid
D029845:Amphibian Proteins; D000838:Anions; D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D018076:DNA, Complementary; D010455:Peptides; D011506:Proteins; C464648:maximin H5, Bombina maxima