Microbial Ecology

, Volume 61, Issue 1, pp 7–12 | Cite as

Viable Real-Time PCR in Environmental Samples: Can All Data Be Interpreted Directly?

  • Mariana Fittipaldi
  • Francesc Codony
  • Barbara Adrados
  • Anne K Camper
  • Jordi Morató
Notes and Short communications


Selective nucleic acid intercalating dyes—ethidium monoazide (EMA) and propidium monoazide (PMA)—represent one of the most successful recent approaches to detect viable cells (as defined by an intact cell membrane) by PCR and have been effectively evaluated in different microorganisms. However, some practical limitations were found, especially in environmental samples. The aim of this work was to show that in the application of viable real-time PCR, there may be significant biases and to propose a strategy for overcoming some of these problems. We present an approach based on the combination of three real-time PCR amplifications for each sample that should provide an improved estimation of the number of viable cells. This approach could be useful especially when it is difficult to determine a priori how to optimize methods using PMA or EMA. Although further studies are required to improve viable real-time PCR methods, the concept as outlined here presents an interesting future research direction.


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Copyright information

© =9Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Mariana Fittipaldi
    • 1
    • 2
  • Francesc Codony
    • 1
  • Barbara Adrados
    • 1
  • Anne K Camper
    • 2
  • Jordi Morató
    • 1
  1. 1.Laboratori de Microbiologia Sanitària i Mediambiental (MSMLab)-Aquasost, UNESCO Chair in Sustainability, Universitat Politècnica de CatalunyaTerrassaSpain
  2. 2.Center for Biofilm EngineeringMontana State UniversityBozemanUSA

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