Polyoxin D inhibits colloidal gold-wheat germ agglutinin labelling of chitin in dimorphic forms of Candida albicans

J Gen Microbiol. 1986 Jun;132(6):1441-51. doi: 10.1099/00221287-132-6-1441.


Yeasts and mycelia of the pathogen Candida albicans grown in the presence of polyoxin D, a competitive inhibitor of chitin synthase, formed chains of swollen bulbous cells as observed by fluorescence microscopy. Wheat germ agglutinin (WGA) complexed to colloidal gold (Au) was used as a specific label at the ultrastructural level to visualize chitin in walls of control and polyoxin-treated cells. In control cells, Au-WGA labelling was preferentially localized in the innermost wall layers and was predominant at bud scars and septa. After 4.5 h in 4 mM-polyoxin D, budding in yeasts and lateral wall growth in mycelia continued, but primary septa failed to form and no Au-WGA labelling was detected in the walls. These results demonstrated that the morphological alterations caused by polyoxin D were due to the absence of chitin, a wall component important for formation of primary septa and for maintenance of structural integrity during morphogenesis.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Antifungal Agents / pharmacology*
  • Candida albicans / drug effects*
  • Candida albicans / ultrastructure
  • Cell Wall / ultrastructure
  • Chitin / metabolism*
  • Gold*
  • Microscopy, Electron
  • Microscopy, Fluorescence
  • Pyrimidine Nucleosides / pharmacology
  • Wheat Germ Agglutinins*


  • Antifungal Agents
  • Pyrimidine Nucleosides
  • Wheat Germ Agglutinins
  • Chitin
  • Gold
  • polyoxorim