title: Interaction of antimicrobial cyclic lipopeptides from Bacillus subtilis influences their effect on spore germination and membrane permeability in fungal plant pathogens.
abstract: Bacillus subtilis cyclic lipopeptides are known to have various antimicrobial effects including different types of interactions with the cell membranes of plant pathogenic fungi. The various spectra of activities of the three main lipopeptide families (fengycins, iturins, and surfactins) seem to be linked to their respective mechanisms of action on the fungal biomembrane. Few studies have shown the combined effect of more than one family of lipopeptides on fungal plant pathogens. In an effort to understand the effect of producing multiple lipopeptide families, sensitivity and membrane permeability of spores from four fungal plant pathogens (Alternaria solani, Fusarium sambucinum, Rhizopus stolonifer, and Verticillium dahliae) were assayed in response to lipopeptides, both individually and as combined treatments. Results showed that inhibition of spores was highly variable depending on the tested fungus-lipopeptide treatment. Results also showed that inhibition of the spores was closely associated with SYTOX stain absorption suggesting effects of efficient treatments on membrane permeability. Combined lipopeptide treatments revealed additive, synergistic or sometimes mutual inhibition of beneficial effects.
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
authors.forename: Jiajie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Hagberg
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
authors.forename: Laura
authors.initials: L
authors.lastname: Novitsky
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
authors.forename: Hanane
authors.initials: H
authors.lastname: Hadj-Moussa
authors.affiliation: Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6. Electronic address: tyler_avis@carleton.ca.
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Avis
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000737:chemistry; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology; D005658:Fungi / Q000187:drug effects* / Q000254:growth & development*; D010456:Peptides, Cyclic / Q000494:pharmacology*; D010539:Permeability / Q000187:drug effects; D010944:Plants / Q000382:microbiology; D013172:Spores, Fungal / Q000187:drug effects* / Q000254:growth & development*
chemical_list: D000935:Antifungal Agents; D010456:Peptides, Cyclic
keywords: Fengycin; Iturin; Mutual inhibition; Surfactin; Synergistic effect