Evaluation of a rapid, quantitative real-time PCR method for enumeration of pathogenic Candida cells in water

Applied and Environmental Microbiology
By: , and 



Quantitative PCR (QPCR) technology, incorporating fluorigenic 5′ nuclease (TaqMan) chemistry, was utilized for the specific detection and quantification of six pathogenic species of Candida (C. albicansC. tropicalisC. kruseiC. parapsilosisC. glabrata and C. lusitaniae) in water. Known numbers of target cells were added to distilled and tap water samples, filtered, and disrupted directly on the membranes for recovery of DNA for QPCR analysis. The assay's sensitivities were between one and three cells per filter. The accuracy of the cell estimates was between 50 and 200% of their true value (95% confidence level). In similar tests with surface water samples, the presence of PCR inhibitory compounds necessitated further purification and/or dilution of the DNA extracts, with resultant reductions in sensitivity but generally not in quantitative accuracy. Analyses of a series of freshwater samples collected from a recreational beach showed positive correlations between the QPCR results and colony counts of the corresponding target species. Positive correlations were also seen between the cell quantities of the target Candida species detected in these analyses and colony counts of Enterococcus organisms. With a combined sample processing and analysis time of less than 4 h, this method shows great promise as a tool for rapidly assessing potential exposures to waterborne pathogenic Candida species from drinking and recreational waters and may have applications in the detection of fecal pollution.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Evaluation of a rapid, quantitative real-time PCR method for enumeration of pathogenic Candida cells in water
Series title Applied and Environmental Microbiology
DOI 10.1128/AEM.69.3.1775-1782.2003
Volume 69
Issue 3
Year Published 2003
Language English
Publisher American Society for Microbiology
Contributing office(s) Great Lakes Science Center
Description 8 p.
First page 1775
Last page 1782
Online Only (Y/N) N
Additional Online Files (Y/N) N