Editor: Gary King
Metal resistance in Candida biofilms
Version of Record online: 5 JAN 2006
FEMS Microbiology Ecology
Volume 55, Issue 3, pages 479–491, March 2006
How to Cite
Harrison, J. J., Rabiei, M., Turner, R. J., Badry, E. A., Sproule, K. M. and Ceri, H. (2006), Metal resistance in Candida biofilms. FEMS Microbiology Ecology, 55: 479–491. doi: 10.1111/j.1574-6941.2005.00045.x
- Issue online: 5 JAN 2006
- Version of Record online: 5 JAN 2006
- Received 27 July 2005; revised 8 September 2005; accepted 8 September 2005.
- Candida tropicalis;
- metal tolerance;
- antifungal resistance;
- extracellular polymeric matrix
Yeasts are often successful in metal-polluted environments; therefore, the ability of biofilm and planktonic cell Candida tropicalis to endure metal toxicity was investigated. Fifteen water-soluble metal ions, chosen to represent groups 6A to 6B of the periodic table, were tested against this organism. With in vitro exposures as long as 24 h, biofilms were up to 65 times more tolerant to killing by metals than corresponding planktonic cultures. Of the most toxic heavy metals tested, only very high concentrations of Hg2+, CrO42− or Cu2+ killed surface-adherent Candida. Metal-chelator precipitates could be formed in biofilms following exposure to the heavy metals Cu2+ and Ni2+. This suggests that Candida biofilms may adsorb metal cations from their surroundings and that sequestration in the extracellular matrix may contribute to resistance. We concluded that biofilm formation may be a strategy for metal resistance and/or tolerance in yeasts.