Five disulfide bridges stabilize a hevein-type antimicrobial peptide from the bark of spindle tree (Euonymus europaeus L.).
A small 45 amino acid residue antifungal polypeptide was isolated from the bark of spindle tree (Euonymus europaeus L.). Though the primary structure of this so-called E. europaeus chitin-binding protein or Ee-CBP is highly similar to the hevein domain, it distinguishes itself from most previously identified hevein-type antimicrobial peptides (AMP) by the presence of two extra cysteine residues that form an extra disulfide bond. Due to these five disulfide bonds Ee-CBP is a remarkably stable protein. Agar diffusion and microtiterplate assays demonstrated that Ee-CBP is a potent antimicrobial protein. IC(50)-values as low as 1 microg/ml were observed for the fungus Botrytis cinerea. Comparative assays further demonstrated that Ee-CBP is a stronger inhibitor of fungal growth than Ac-AMP2 from Amaranthus caudatus seeds, which is considered one of the most potent antifungal hevein-type plant proteins.
Van den Bergh
Karolien P B
KP
Laboratory of Phytopathology and Plant Protection, Katholieke Universiteit Leuven, Willem de Croylaan 42, Belgium.
Proost
Paul
P
Van Damme
Jo
J
Coosemans
Jozef
J
Van Damme
Els J M
EJ
Peumans
Willy J
WJ
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides; D004220:Disulfides / Q000737:chemistry*; D029756:Euonymus / Q000737:chemistry*; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D024301:Plant Bark / Q000737:chemistry*; D037121:Plant Lectins / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid
D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D004220:Disulfides; D037121:Plant Lectins; C045875:hevein