Microbiologic quality of an untreated water sample analyzed by a novel DNA chip for simultaneous detection of microorganisms

Consumption of contaminated drinking water heavily contributes to the burden of gastrointestinal waterborne diseases. Conventional detection methodologies present several shortcomings, such as indirect measure of indicator species, low throughput and time consume. DNA chips have the potential to serve as surveillance systems for the simultaneous detection of pathogens overcoming these limitations. We have developed a DNA chip for simultaneous detection of multiple waterborne pathogens. Species specific DNA probes were implemented on a microarray, for microorganism detection. Present study reports the results of one untreated water sample analyzed by conventional methods and by the DNA chip. The results were concordant for the mandatory organisms (total coliforms, Escherichia coli, fecal enterococci) using both methods, reinforcing the utility and proof-ofconcept of the DNA chip. However, it is necessary a prior enrichment in a culture medium in order to obtain a positive signal using the DNA chip. The DNA chip may be a valuable distinctive tool for waterborne pathogens detection