New insights into membrane-active action in plasma membrane of fungal hyphae by the lipopeptide antibiotic bacillomycin L

Biochim Biophys Acta. 2013 Sep;1828(9):2230-7. doi: 10.1016/j.bbamem.2013.05.033. Epub 2013 Jun 10.

Abstract

Bacillomycin L, a natural iturinic lipopeptide produced by Bacillus amyloliquefaciens, is characterized by strong antifungal activities against a variety of agronomically important filamentous fungi including Rhizoctonia solani Kühn. Prior to this study, the role of membrane permeabilization in the antimicrobial activity of bacillomycin L against plant pathogenic fungi had not been investigated. To shed light on the mechanism of this antifungal activity, the permeabilization of R. solani hyphae by bacillomycin L was investigated and compared with that by amphotericin B, a polyene antibiotic which is thought to act primarily through membrane disruption. Our results derived from electron microscopy, various fluorescent techniques and gel retardation experiments revealed that the antifungal activity of bacillomycin L may be not solely a consequence of fungal membrane permeabilization, but related to the interaction of it with intracellular targets. Our findings provide more insights into the mode of action of bacillomycin L and other iturins, which could in turn help to develop new or improved antifungal formulations or result in novel strategies to prevent fungal spoilage.

Keywords: Bacillomycin L; Iturin; Mechanism of action; Membrane permeabilization; Rhizoctonia solani Kühn.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amphotericin B / chemistry
  • Amphotericin B / pharmacology
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology
  • Cell Membrane / chemistry*
  • Cell Membrane / drug effects
  • Cell Membrane Permeability
  • Dose-Response Relationship, Drug
  • Electrophoretic Mobility Shift Assay
  • Hyphae / chemistry*
  • Hyphae / drug effects
  • Microbial Sensitivity Tests
  • Microscopy, Electron
  • Peptides, Cyclic / chemistry
  • Peptides, Cyclic / pharmacology
  • Rhizoctonia / chemistry*
  • Rhizoctonia / drug effects

Substances

  • Anti-Bacterial Agents
  • Peptides, Cyclic
  • bacillomycin L
  • Amphotericin B