, 164:301 | Cite as

Inhibition on Candida albicans biofilm formation using divalent cation chelators (EDTA)

  • Gordon Ramage
  • Brian L. Wickes
  • José L. López-RibotEmail author


Candida albicans can readily form biofilms on both inanimate and biological surfaces. In this study we investigated a means of inhibiting biofilm formation using EDTA (Ethylenediaminetetra-acetic acid), a divalent cation chelating agent, which has been shown to affect C. albicans filamentation. Candida albicans biofilms were formed in 96-well microtitre plates. Cells were allowed to adhere for 1, 2, and 4 h at 37°C, washed in PBS, and then treated with different concentrations of EDTA (0, 2.5, 25, and 250 mM). EDTA was also added to the standardized suspension prior to adding to the microtiter plate and to a preformed 24 h biofilm. All plates were then incubated at 37°C for an additional 24 h to allow for biofilm formation. The extent and characteristics of biofilm formation were then microscopically assessed and with a semi-quantitative colorimetric technique based on the use of an XTT-reduction assay. Northern blot analysis of the hyphal wall protein (HWP1) expression was also monitored in planktonic and biofilm cells treated with EDTA. Microscopic analysis and colorimetric readings revealed that filamentation and biofilm formation were inhibited by EDTA in a concentration dependant manner. However, preformed biofilms were minimally affected by EDTA (maximum of 31% reduction at 250 mM). The HWP1 gene expression was reduced in EDTA-treated planktonic and biofilm samples. These results indicate that EDTA inhibits C. albicans biofilm formation are most likely through its inhibitory effect on filamentation and indicates the potential therapeutic effects of EDTA. This compound may serve a non-toxic means of preventing biofilm formation on infections with a C. albicans biofilm etiology.


Candida albicans EDTA Biofilm 



Gordon Ramage is the recipient of an International Association for Dental Research (IADR)/GlaxoSmithKline (GSK) award for Oral Innovation. José L. López-Ribot was the recipient of a New Investigator Award in Molecular Pathogenic Mycology from the Burroughs Wellcome Fund. This work was supported by grant ATP 3659-0080 from the Texas Higher Education Coordinating Board (Advance Technology Program, Biomedicine).


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  • Gordon Ramage
    • 1
  • Brian L. Wickes
    • 2
  • José L. López-Ribot
    • 3
    Email author
  1. 1.Section of Infection and Immunity, Glasgow Dental School and HospitalThe University of GlasgowGlasgowUK
  2. 2.Department of MicrobiologyThe University of Texas Health Science Center at San AntonioSan AntonioUSA
  3. 3.Department of Biology and South Texas Center for Emerging Infectious DiseasesThe University of Texas at San AntonioSan AntonioUSA

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