title: Vicilin-like peptides from Capsicum baccatum L. seeds are α-amylase inhibitors and exhibit antifungal activity against important yeasts in medical mycology.
abstract: The objective of this study was to isolate antimicrobial peptides from Capsicum baccatum seeds and evaluate their antimicrobial activity and inhibitory effects against α-amylase. Initially, proteins from the flour of C. baccatum seeds were extracted in sodium phosphate buffer, pH 5.4, and precipitated with ammonium sulfate at 90% saturation. The D1 and D2 fractions were subjected to antifungal tests against the yeasts Saccharomyces cerevisiae, Candida albicans, Candida tropicalis, and Kluyveromyces marxiannus, and tested against α-amylases from Callosobruchus maculates and human saliva. The D2 fraction presented higher antimicrobial activity and was subjected to further purification and seven new different fractions (H1-H7) were obtained. Peptides in the H4 fraction were sequenced and the N-terminal sequences revealed homology with previously reported storage vicilins from seeds. The H4 fraction exhibited strong antifungal activity and also promoted morphological changes in yeast, including pseudohyphae formation. All fractions, including H4, inhibited mammalian α-amylase activity but only the H4 fraction was able to inhibit C. maculatus α-amylase activity. These results suggest that the fractions isolated from the seeds of C. baccatum can act directly in plant defenses against pathogens and insects.
authors.affiliation: Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, 28015-602, RJ, Brazil.
authors.forename: Gabriela C
authors.initials: GC
authors.lastname: Vieira Bard
authors.forename: Viviane V
authors.initials: VV
authors.lastname: Nascimento
authors.forename: Antônia Elenir A
authors.initials: AE
authors.lastname: Oliveira
authors.forename: Rosana
authors.initials: R
authors.lastname: Rodrigues
authors.forename: Maura
authors.initials: M
authors.lastname: Da Cunha
authors.forename: Germana B
authors.initials: GB
authors.lastname: Dias
authors.forename: Ilka M
authors.initials: IM
authors.lastname: Vasconcelos
authors.forename: Andre O
authors.initials: AO
authors.lastname: Carvalho
authors.forename: Valdirene M
authors.initials: VM
authors.lastname: Gomes
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000935:Antifungal Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002212:Capsicum / Q000737:chemistry*; D002852:Chromatography, Ion Exchange; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007313:Insecta; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009172:Mycology; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D055314:Seed Storage Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D012639:Seeds / Q000737:chemistry*; D016415:Sequence Alignment; D015003:Yeasts / Q000187:drug effects* / Q000254:growth & development; D000516:alpha-Amylases / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D004791:Enzyme Inhibitors; D010455:Peptides; D055314:Seed Storage Proteins; C100817:vicilin-like protein, plant; D000516:alpha-Amylases
keywords: Capsicum baccatum; antimicrobial peptides; vicilin; yeasts