Differential toxicity of antifungal protein AFP against mutants of "Fusarium oxysporum"

  1. Magdalena Martín Urdiroz
  2. Ana L. Martínez Rocha
  3. Antonio Di Pietro
  4. Alvaro Martínez del Pozo
  5. María Isabel G. Roncero
Revista:
International microbiology: official journal of the Spanish Society for Microbiology

ISSN: 1618-1905

Año de publicación: 2009

Volumen: 12

Número: 2

Páginas: 115-121

Tipo: Artículo

Otras publicaciones en: International microbiology: official journal of the Spanish Society for Microbiology

Resumen

Antifungal protein (AFP) from Aspergillus giganteus was assayed for toxicity against the Fusarium oxysporum wild-type strain and mutants in genes involved in cell signaling (ÄpacC, pacCc Äfmk1) or cell-wall biogenesis (ÄchsV, Ächs7, Ägas1). The mutants were classified into two groups according to their sensitivity to AFP: ÄpacC, Ägas1 and Ächs7, which were significantly more resistant to AFP than the wild-type, and pacCC, Äfmk1 and ÄchsV, which were more sensitive. Western blot analysis revealed increased binding of AFP to the three resistant mutants, ÄpacC, Ägas1 and Ächs7, but also to ÄchsV, indicating that differential binding may not be a key determinant for sensitivity. Addition of Ca2+ or K+ dramatically reduced antifungal activity and binding of AFP, suggesting that these cations compete for the same targets as AFP at the surface of the fungal cell. [Int Microbiol 2009; 12(2):115-121]