Article

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

Section of Infection and Immunity, Glasgow Dental School and Hospital, The University of Glasgow, Glasgow, UK.
Mycopathologia (Impact Factor: 1.53). 01/2008; 164(6):301-6. DOI: 10.1007/s11046-007-9068-x
Source: PubMed

ABSTRACT

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 degrees 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 degrees 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 dependent 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.

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    • "The divalent chelating capacity of EDTA causes lipopolysaccharides to separate from the outer membrane of microbial cells, thus increasing the membrane permeability and subsequently cell death (Gray and Wilkinson, 1965;Banin et al., 2006;Yakandawala et al., 2007;Saadat et al., 2013). For these reasons, EDTA has been used in food and therapeutic industry to eradicate microbes and their biofilm formation (Ramage et al., 2007;Juda et al., 2008;Chauhan et al., 2012;Shaikh and Musaddiq, 2012). In this study, we tested the role of EDTA in stimulating bacterial respiration and oil biodegradation in an oil-polluted desert soil subjected to a bioaugmentation treatment. "
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