title: Antifungal activity of plant defensin AFP1 in Brassica juncea involves the recognition of the methyl residue in glucosylceramide of target pathogen Candida albicans.
abstract: An antifungal defensin, AFP1, of Brassica juncea inhibits the growth of various microorganisms. The molecular details of this inhibition remain largely unknown. Herein, we reveal that a specific structure of fungal sphingolipid glucosylceramide (GlcCer) is critical for the sensitivity of Candida albicans cells to AFP1. Our results revealed that AFP1 induces plasma membrane permeabilization and the production of reactive oxygen species (ROS) in wild-type C. albicans cells, but not in cells lacking the ninth methyl residue of the GlcCer sphingoid base moiety, which is a characteristic feature of fungi. AFP1-induced ROS production is responsible for its antifungal activity, with a consequent loss of yeast cell viability. These findings suggest that AFP1 specifically recognizes the structural difference of GlcCer for targeting of the fungal pathogens.
authors.affiliation: Department of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, 265-1 Higashijima, Akiha-ku, Niigata, 956-8603, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Oguro
authors.forename: Harutake
authors.initials: H
authors.lastname: Yamazaki
authors.forename: Masamichi
authors.initials: M
authors.lastname: Takagi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Takaku
mesh_terms: D000935:Antifungal Agents / Q000378:metabolism; D002176:Candida albicans / Q000187:drug effects* / Q000472:pathogenicity; D023082:Defensins / Q000235:genetics / Q000378:metabolism*; D005963:Glucosylceramides / Q000235:genetics / Q000378:metabolism; D009149:Mustard Plant / Q000235:genetics / Q000254:growth & development*; D010935:Plant Diseases / Q000235:genetics*; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D023082:Defensins; D005963:Glucosylceramides; D017382:Reactive Oxygen Species