Antimicrobial peptides from chili pepper seeds causes yeast plasma membrane permeabilization and inhibits the acidification of the medium by yeast cells.
During the last few years, a growing number of cysteine-rich antimicrobial peptides has been isolated from plants and particularly from seeds. It has become increasingly clear that these peptides play an important role in the protection of plants against microbial infection. In this work, proteins from chili pepper (Capsicum annuum L.) seeds were extracted in phosphate buffer, pH 5.4 and peptides purification were performed by employing ion-exchange chromatographies on DEAE, CM-Sepharose, Sephacryl S-100 and reverse phase in HPLC. Three peptide enriched fractions, namely F1, F2 and F3, were obtained after the CM-Sepharose chromatography. The F1 fraction, mainly composed of three peptides ranging from 6 to 10 kDa, was submitted to N-terminal amino acid sequencing. The closer to 10 kDa peptide showed high sequence homology to lipid transfer proteins (LTPs) previously isolated from others seeds. F1 fraction exhibited strong fungicidal activity against Candida albicans, Saccharomyces cerevisiae and Schizosaccharomyces pombe and also promoted several morphological changes to C. albicans, including the formation of pseudohyphae, as revealed by scanning electron micrography. F1 fraction also reduced the glucose stimulated acidification of the medium mediated by H(+)-ATPase of S. cerevisiae cells in a dose-dependent manner and caused the permeabilization of yeast plasma membrane to the dye SYTOX Green, as verified by confocal laser microscopy.
Diz
Mariângela S S
MS
Universidade Estadual do Norte Fluminense, Centro de Biociências e Biotecnologia, Campos dos Goytacazes, 28015-602 RJ, Brazil.
Carvalho
André O
AO
Rodrigues
Rosana
R
Neves-Ferreira
Ana Gisele C
AG
Da Cunha
Maura
M
Alves
Elias Walter
EW
Okorokova-Façanha
Anna L
AL
Oliveira
Marco Antônio
MA
Perales
Jonas
J
Machado
Olga L T
OL
Gomes
Valdirene M
VM
D000143:Acids / Q000737:chemistry; D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D002212:Capsicum / Q000737:chemistry*; D002463:Cell Membrane Permeability / Q000187:drug effects*; D049109:Cell Proliferation; D003470:Culture Media; D005947:Glucose / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D010940:Plant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D012639:Seeds / Q000737:chemistry*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D015003:Yeasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D000143:Acids; D000935:Antifungal Agents; D003470:Culture Media; D010455:Peptides; D010940:Plant Proteins; D005947:Glucose