Different anti-Candida activities of two human lactoferrin-derived peptides, Lfpep and kaliocin-1.
The synthetic peptides Lfpep and kaliocin-1 include the sequences from positions 18 to 40 and 153 to 183 of human lactoferrin, respectively. Lfpep is a cationic peptide with bactericidal and giardicidal effects, whereas kaliocin-1 is a novel bactericidal peptide that corresponds to a highly homologous sequence present in the transferrin family of proteins. Both peptides presented fungicidal activity against Candida spp., including fluconazole- and amphotericin B-resistant clinical isolates. Lfpep exhibited higher antifungal activity (8- to 30-fold) and salt resistance than kaliocin-1. The killing activity of Lfpep was mediated by its permeabilizing activity on Candida albicans cells, whereas kaliocin-1 was unable to disrupt the cytoplasmic membrane, as indicated by its inability to allow permeation of propidium iodide and the small amount of K+ released. The amino acid sequence of kaliocin-1 includes the "multidimensional antimicrobial signature" conserved in disulfide-containing antimicrobial peptides and a striking similarity to brevinin-1Sa, an antimicrobial peptide from frog skin secretions, exhibiting a "Rana box"-like sequence. These features may be of interest in the design of new antifungals.
Department of Functional Biology (Microbiology), Faculty of Medicine, University of Oviedo, C/ Julian Claveria, 6, 33006 Oviedo, Spain.
Mónica
M
Viejo-Díaz
María T
MT
Andrés
José F
JF
Fierro
D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000737:chemistry; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects*; D002462:Cell Membrane / Q000187:drug effects; D006801:Humans; D007781:Lactoferrin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D016415:Sequence Alignment
D029845:Amphibian Proteins; D000935:Antifungal Agents; D023181:Antimicrobial Cationic Peptides; C403330:Lfpep peptide; C078413:brevinin-1 protein, Rana; D007781:Lactoferrin